# tzdb data for North and Central America and environs # This file is in the public domain, so clarified as of # 2009-05-17 by Arthur David Olson. # also includes Central America and the Caribbean # This file is by no means authoritative; if you think you know better, # go ahead and edit the file (and please send any changes to # tz@iana.org for general use in the future). For more, please see # the file CONTRIBUTING in the tz distribution. # From Paul Eggert (1999-03-22): # A reliable and entertaining source about time zones is # Derek Howse, Greenwich time and longitude, Philip Wilson Publishers (1997). ############################################################################### # United States # From Paul Eggert (1999-03-31): # Howse writes (pp 121-125) that time zones were invented by # Professor Charles Ferdinand Dowd (1825-1904), # Principal of Temple Grove Ladies' Seminary (Saratoga Springs, NY). # His pamphlet "A System of National Time for Railroads" (1870) # was the result of his proposals at the Convention of Railroad Trunk Lines # in New York City (1869-10). His 1870 proposal was based on Washington, DC, # but in 1872-05 he moved the proposed origin to Greenwich. # From Paul Eggert (2018-03-20): # Dowd's proposal left many details unresolved, such as where to draw # lines between time zones. The key individual who made time zones # work in the US was William Frederick Allen - railway engineer, # managing editor of the Travelers' Guide, and secretary of the # General Time Convention, a railway standardization group. Allen # spent months in dialogs with scientific and railway leaders, # developed a workable plan to institute time zones, and presented it # to the General Time Convention on 1883-04-11, saying that his plan # meant "local time would be practically abolished" - a plus for # railway scheduling. By the next convention on 1883-10-11 nearly all # railroads had agreed and it took effect on 1883-11-18. That Sunday # was called the "day of two noons", as some locations observed noon # twice. Allen witnessed the transition in New York City, writing: # # I heard the bells of St. Paul's strike on the old time. Four # minutes later, obedient to the electrical signal from the Naval # Observatory ... the time-ball made its rapid descent, the chimes # of old Trinity rang twelve measured strokes, and local time was # abandoned, probably forever. # # Most of the US soon followed suit. See: # Bartky IR. The adoption of standard time. Technol Cult 1989 Jan;30(1):25-56. # https://dx.doi.org/10.2307/3105430 # From Paul Eggert (2005-04-16): # That 1883 transition occurred at 12:00 new time, not at 12:00 old time. # See p 46 of David Prerau, Seize the daylight, Thunder's Mouth Press (2005). # From Paul Eggert (2006-03-22): # A good source for time zone historical data in the US is # Thomas G. Shanks, The American Atlas (5th edition), # San Diego: ACS Publications, Inc. (1991). # Make sure you have the errata sheet; the book is somewhat useless without it. # It is the source for most of the pre-1991 US entries below. # From Paul Eggert (2001-03-06): # Daylight Saving Time was first suggested as a joke by Benjamin Franklin # in his whimsical essay "An Economical Project for Diminishing the Cost # of Light" published in the Journal de Paris (1784-04-26). # Not everyone is happy with the results: # # I don't really care how time is reckoned so long as there is some # agreement about it, but I object to being told that I am saving # daylight when my reason tells me that I am doing nothing of the kind. # I even object to the implication that I am wasting something # valuable if I stay in bed after the sun has risen. As an admirer # of moonlight I resent the bossy insistence of those who want to # reduce my time for enjoying it. At the back of the Daylight Saving # scheme I detect the bony, blue-fingered hand of Puritanism, eager # to push people into bed earlier, and get them up earlier, to make # them healthy, wealthy and wise in spite of themselves. # # -- Robertson Davies, The diary of Samuel Marchbanks, # Clarke, Irwin (1947), XIX, Sunday # # For more about the first ten years of DST in the United States, see # Robert Garland, Ten years of daylight saving from the Pittsburgh standpoint # (Carnegie Library of Pittsburgh, 1927). # https://web.archive.org/web/20160517155308/http://www.clpgh.org/exhibit/dst.html # # Shanks says that DST was called "War Time" in the US in 1918 and 1919. # However, DST was imposed by the Standard Time Act of 1918, which # was the first nationwide legal time standard, and apparently # time was just called "Standard Time" or "Daylight Saving Time". # From Paul Eggert (2019-06-04): # Here is the legal basis for the US federal rules. # * Public Law 65-106 (1918-03-19) implemented standard and daylight saving # time for the first time across the US, springing forward on March's last # Sunday and falling back on October's last Sunday. # https://www.loc.gov/law/help/statutes-at-large/65th-congress/session-2/c65s2ch24.pdf # * Public Law 66-40 (1919-08-20) repealed DST on October 1919's last Sunday. # https://www.loc.gov/law/help/statutes-at-large/66th-congress/session-1/c66s1ch51.pdf # * Public Law 77-403 (1942-01-20) started wartime DST on 1942-02-09. # https://www.loc.gov/law/help/statutes-at-large/77th-congress/session-2/c77s2ch7.pdf # * Public Law 79-187 (1945-09-25) ended wartime DST on 1945-09-30. # https://www.loc.gov/law/help/statutes-at-large/79th-congress/session-1/c79s1ch388.pdf # * Public Law 89-387 (1966-04-13) reinstituted a national standard for DST, # from April's last Sunday to October's last Sunday, effective 1967. # https://www.govinfo.gov/content/pkg/STATUTE-80/pdf/STATUTE-80-Pg107.pdf # * Public Law 93-182 (1973-12-15) moved the 1974 spring-forward to 01-06. # https://www.govinfo.gov/content/pkg/STATUTE-87/pdf/STATUTE-87-Pg707.pdf # * Public Law 93-434 (1974-10-05) moved the 1975 spring-forward to # February's last Sunday. # https://www.govinfo.gov/content/pkg/STATUTE-88/pdf/STATUTE-88-Pg1209.pdf # * Public Law 99-359 (1986-07-08) moved the spring-forward to April's first # Sunday. # https://www.govinfo.gov/content/pkg/STATUTE-100/pdf/STATUTE-100-Pg764.pdf # * Public Law 109-58 (2005-08-08), effective 2007, moved the spring-forward # to March's second Sunday and the fall-back to November's first Sunday. # https://www.govinfo.gov/content/pkg/PLAW-109publ58/pdf/PLAW-109publ58.pdf # All transitions are at 02:00 local time. # From Arthur David Olson: # Before the Uniform Time Act of 1966 took effect in 1967, observance of # Daylight Saving Time in the US was by local option, except during wartime. # From Arthur David Olson (2000-09-25): # Last night I heard part of a rebroadcast of a 1945 Arch Oboler radio drama. # In the introduction, Oboler spoke of "Eastern Peace Time." # An AltaVista search turned up: # https://web.archive.org/web/20000926032210/http://rowayton.org/rhs/hstaug45.html # "When the time is announced over the radio now, it is 'Eastern Peace # Time' instead of the old familiar 'Eastern War Time.' Peace is wonderful." # (August 1945) by way of confirmation. # # From Paul Eggert (2017-09-23): # This was the V-J Day issue of the Clamdigger, a Rowayton, CT newsletter. # From Joseph Gallant citing # George H. Douglas, _The Early Days of Radio Broadcasting_ (1987): # At 7 P.M. (Eastern War Time) [on 1945-08-14], the networks were set # to switch to London for Attlee's address, but the American people # never got to hear his speech live. According to one press account, # CBS' Bob Trout was first to announce the word of Japan's surrender, # but a few seconds later, NBC, ABC and Mutual also flashed the word # of surrender, all of whom interrupting the bells of Big Ben in # London which were to precede Mr. Attlee's speech. # From Paul Eggert (2003-02-09): It was Robert St John, not Bob Trout. From # Myrna Oliver's obituary of St John on page B16 of today's Los Angeles Times: # # ... a war-weary U.S. clung to radios, awaiting word of Japan's surrender. # Any announcement from Asia would reach St. John's New York newsroom on a # wire service teletype machine, which had prescribed signals for major news. # Associated Press, for example, would ring five bells before spewing out # typed copy of an important story, and 10 bells for news "of transcendental # importance." # # On Aug. 14, stalling while talking steadily into the NBC networks' open # microphone, St. John heard five bells and waited only to hear a sixth bell, # before announcing confidently: "Ladies and gentlemen, World War II is over. # The Japanese have agreed to our surrender terms." # # He had scored a 20-second scoop on other broadcasters. # From Arthur David Olson (2005-08-22): # Paul has been careful to use the "US" rules only in those locations # that are part of the United States; this reflects the real scope of # U.S. government action. So even though the "US" rules have changed # in the latest release, other countries won't be affected. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule US 1918 1919 - Mar lastSun 2:00 1:00 D Rule US 1918 1919 - Oct lastSun 2:00 0 S Rule US 1942 only - Feb 9 2:00 1:00 W # War Rule US 1945 only - Aug 14 23:00u 1:00 P # Peace Rule US 1945 only - Sep 30 2:00 0 S Rule US 1967 2006 - Oct lastSun 2:00 0 S Rule US 1967 1973 - Apr lastSun 2:00 1:00 D Rule US 1974 only - Jan 6 2:00 1:00 D Rule US 1975 only - Feb lastSun 2:00 1:00 D Rule US 1976 1986 - Apr lastSun 2:00 1:00 D Rule US 1987 2006 - Apr Sun>=1 2:00 1:00 D Rule US 2007 max - Mar Sun>=8 2:00 1:00 D Rule US 2007 max - Nov Sun>=1 2:00 0 S # From Arthur David Olson, 2005-12-19 # We generate the files specified below to guard against old files with # obsolete information being left in the time zone binary directory. # We limit the list to names that have appeared in previous versions of # this time zone package. # We do these as separate Zones rather than as Links to avoid problems if # a particular place changes whether it observes DST. # We put these specifications here in the northamerica file both to # increase the chances that they'll actually get compiled and to # avoid the need to duplicate the US rules in another file. # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone EST -5:00 - EST Zone MST -7:00 - MST Zone HST -10:00 - HST Zone EST5EDT -5:00 US E%sT Zone CST6CDT -6:00 US C%sT Zone MST7MDT -7:00 US M%sT Zone PST8PDT -8:00 US P%sT # From U. S. Naval Observatory (1989-01-19): # USA EASTERN 5 H BEHIND UTC NEW YORK, WASHINGTON # USA EASTERN 4 H BEHIND UTC APR 3 - OCT 30 # USA CENTRAL 6 H BEHIND UTC CHICAGO, HOUSTON # USA CENTRAL 5 H BEHIND UTC APR 3 - OCT 30 # USA MOUNTAIN 7 H BEHIND UTC DENVER # USA MOUNTAIN 6 H BEHIND UTC APR 3 - OCT 30 # USA PACIFIC 8 H BEHIND UTC L.A., SAN FRANCISCO # USA PACIFIC 7 H BEHIND UTC APR 3 - OCT 30 # USA ALASKA STD 9 H BEHIND UTC MOST OF ALASKA (AKST) # USA ALASKA STD 8 H BEHIND UTC APR 3 - OCT 30 (AKDT) # USA ALEUTIAN 10 H BEHIND UTC ISLANDS WEST OF 170W # USA " 9 H BEHIND UTC APR 3 - OCT 30 # USA HAWAII 10 H BEHIND UTC # USA BERING 11 H BEHIND UTC SAMOA, MIDWAY # From Arthur David Olson (1989-01-21): # The above dates are for 1988. # Note the "AKST" and "AKDT" abbreviations, the claim that there's # no DST in Samoa, and the claim that there is DST in Alaska and the # Aleutians. # From Arthur David Olson (1988-02-13): # Legal standard time zone names, from United States Code (1982 Edition and # Supplement III), Title 15, Chapter 6, Section 260 and forward. First, names # up to 1967-04-01 (when most provisions of the Uniform Time Act of 1966 # took effect), as explained in sections 263 and 261: # (none) # United States standard eastern time # United States standard mountain time # United States standard central time # United States standard Pacific time # (none) # United States standard Alaska time # (none) # Next, names from 1967-04-01 until 1983-11-30 (the date for # public law 98-181): # Atlantic standard time # eastern standard time # central standard time # mountain standard time # Pacific standard time # Yukon standard time # Alaska-Hawaii standard time # Bering standard time # And after 1983-11-30: # Atlantic standard time # eastern standard time # central standard time # mountain standard time # Pacific standard time # Alaska standard time # Hawaii-Aleutian standard time # Samoa standard time # The law doesn't give abbreviations. # # From Paul Eggert (2016-12-19): # Here are URLs for the 1918 and 1966 legislation: # http://uscode.house.gov/statviewer.htm?volume=40&page=451 # http://uscode.house.gov/statviewer.htm?volume=80&page=108 # Although the 1918 names were officially "United States Standard # Eastern Time" and similarly for "Central", "Mountain", "Pacific", # and "Alaska", in practice "Standard" was placed just before "Time", # as codified in 1966. In practice, Alaska time was abbreviated "AST" # before 1968. Summarizing the 1967 name changes: # 1918 names 1967 names # -08 Standard Pacific Time (PST) Pacific standard time (PST) # -09 (unofficial) Yukon (YST) Yukon standard time (YST) # -10 Standard Alaska Time (AST) Alaska-Hawaii standard time (AHST) # -11 (unofficial) Nome (NST) Bering standard time (BST) # # From Paul Eggert (2023-01-23), from a 2001-01-08 heads-up from Rives McDow: # Public law 106-564 (2000-12-23) introduced "Chamorro standard time" # for time in Guam and the Northern Marianas. See the file "australasia". # Also see 15 U.S.C. §263 . # # From Paul Eggert (2015-04-17): # HST and HDT are standardized abbreviations for Hawaii-Aleutian # standard and daylight times. See section 9.47 (p 234) of the # U.S. Government Printing Office Style Manual (2008) # https://www.gpo.gov/fdsys/pkg/GPO-STYLEMANUAL-2008/pdf/GPO-STYLEMANUAL-2008.pdf # From Arthur David Olson, 2005-08-09 # The following was signed into law on 2005-08-08. # # H.R. 6, Energy Policy Act of 2005, SEC. 110. DAYLIGHT SAVINGS. # (a) Amendment.--Section 3(a) of the Uniform Time Act of 1966 (15 # U.S.C. 260a(a)) is amended-- # (1) by striking "first Sunday of April" and inserting "second # Sunday of March"; and # (2) by striking "last Sunday of October" and inserting "first # Sunday of November'. # (b) Effective Date.--Subsection (a) shall take effect 1 year after the # date of enactment of this Act or March 1, 2007, whichever is later. # (c) Report to Congress.--Not later than 9 months after the effective # date stated in subsection (b), the Secretary shall report to Congress # on the impact of this section on energy consumption in the United # States. # (d) Right to Revert.--Congress retains the right to revert the # Daylight Saving Time back to the 2005 time schedules once the # Department study is complete. # US eastern time, represented by New York # Connecticut, Delaware, District of Columbia, most of Florida, # Georgia, southeast Indiana (Dearborn and Ohio counties), eastern Kentucky # (except America/Kentucky/Louisville below), Maine, Maryland, Massachusetts, # New Hampshire, New Jersey, New York, North Carolina, Ohio, # Pennsylvania, Rhode Island, South Carolina, eastern Tennessee, # Vermont, Virginia, West Virginia # From Dave Cantor (2004-11-02): # Early this summer I had the occasion to visit the Mount Washington # Observatory weather station atop (of course!) Mount Washington [, NH].... # One of the staff members said that the station was on Eastern Standard Time # and didn't change their clocks for Daylight Saving ... so that their # reports will always have times which are 5 hours behind UTC. # From Paul Eggert (2005-08-26): # According to today's Huntsville Times # http://www.al.com/news/huntsvilletimes/index.ssf?/base/news/1125047783228320.xml&coll=1 # a few towns on Alabama's "eastern border with Georgia, such as Phenix City # in Russell County, Lanett in Chambers County and some towns in Lee County, # set their watches and clocks on Eastern time." It quotes H.H. "Bubba" # Roberts, city administrator in Phenix City. as saying "We are in the Central # time zone, but we do go by the Eastern time zone because so many people work # in Columbus." # # From Paul Eggert (2017-02-22): # Four cities are involved. The two not mentioned above are Smiths Station # and Valley. Barbara Brooks, Valley's assistant treasurer, heard it started # because West Point Pepperell textile mills were in Alabama while the # corporate office was in Georgia, and residents voted to keep Eastern # time even after the mills closed. See: Kazek K. Did you know which # Alabama towns are in a different time zone? al.com 2017-02-06. # http://www.al.com/living/index.ssf/2017/02/do_you_know_which_alabama_town.html # From Paul Eggert (2014-09-06): # Monthly Notices of the Royal Astronomical Society 44, 4 (1884-02-08), 208 # says that New York City Hall time was 3 minutes 58.4 seconds fast of # Eastern time (i.e., -4:56:01.6) just before the 1883 switch. # Rule NAME FROM TO - IN ON AT SAVE LETTER Rule NYC 1920 only - Mar lastSun 2:00 1:00 D Rule NYC 1920 only - Oct lastSun 2:00 0 S Rule NYC 1921 1966 - Apr lastSun 2:00 1:00 D Rule NYC 1921 1954 - Sep lastSun 2:00 0 S Rule NYC 1955 1966 - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] #STDOFF -4:56:01.6 Zone America/New_York -4:56:02 - LMT 1883 Nov 18 17:00u -5:00 US E%sT 1920 -5:00 NYC E%sT 1942 -5:00 US E%sT 1946 -5:00 NYC E%sT 1967 -5:00 US E%sT # US central time, represented by Chicago # Alabama, Arkansas, Florida panhandle (Bay, Calhoun, Escambia, # Gulf, Holmes, Jackson, Okaloosa, Santa Rosa, Walton, and # Washington counties), Illinois, western Indiana # (Gibson, Jasper, Lake, LaPorte, Newton, Porter, Posey, Spencer, # Vanderburgh, and Warrick counties), Iowa, most of Kansas, western # Kentucky, Louisiana, Minnesota, Mississippi, Missouri, eastern # Nebraska, eastern North Dakota, Oklahoma, eastern South Dakota, # western Tennessee, most of Texas, Wisconsin # From Paul Eggert (2018-01-07): # In 1869 the Chicago Astronomical Society contracted with the city to keep # time. Though delayed by the Great Fire, by 1880 a wire ran from the # Dearborn Observatory (on the University of Chicago campus) to City Hall, # which then sent signals to police and fire stations. However, railroads got # their time signals from the Allegheny Observatory, the Madison Observatory, # the Ann Arbor Observatory, etc., so their clocks did not agree with each # other or with the city's official time. The confusion took some years to # clear up. See: # Moser M. How Chicago gave America its time zones. Chicago. 2018-01-04. # http://www.chicagomag.com/city-life/January-2018/How-Chicago-Gave-America-Its-Time-Zones/ # From Larry M. Smith (2006-04-26) re Wisconsin: # https://docs.legis.wisconsin.gov/statutes/statutes/175.pdf # is currently enforced at the 01:00 time of change. Because the local # "bar time" in the state corresponds to 02:00, a number of citations # are issued for the "sale of class 'B' alcohol after prohibited # hours" within the deviated hour of this change every year.... # # From Douglas R. Bomberg (2007-03-12): # Wisconsin has enacted (nearly eleventh-hour) legislation to get WI # Statue 175 closer in synch with the US Congress' intent.... # https://docs.legis.wisconsin.gov/2007/related/acts/3 # From an email administrator of the City of Fort Pierre, SD (2015-12-21): # Fort Pierre is technically located in the Mountain time zone as is # the rest of Stanley County. Most of Stanley County and Fort Pierre # uses the Central time zone due to doing most of their business in # Pierre so it simplifies schedules. I have lived in Stanley County # all my life and it has been that way since I can remember. (43 years!) # # From Paul Eggert (2015-12-25): # Assume this practice predates 1970, so Fort Pierre can use America/Chicago. # From Paul Eggert (2015-04-06): # In 1950s Nashville a public clock had dueling faces, one for conservatives # and the other for liberals; the two sides didn't agree about the time of day. # I haven't found a photo of this clock, nor have I tracked down the TIME # magazine report cited below, but here's the story as told by the late # American journalist John Seigenthaler, who was there: # # "The two [newspaper] owners held strongly contrasting political and # ideological views. Evans was a New South liberal, Stahlman an Old South # conservative, and their two papers frequently clashed editorially, often on # the same day.... In the 1950s as the state legislature was grappling with # the question of whether to approve daylight saving time for the entire state, # TIME magazine reported: # # "'The Nashville Banner and The Nashville Tennessean rarely agree on anything # but the time of day - and last week they couldn't agree on that.' # # "It was all too true. The clock on the front of the building had two faces - # The Tennessean side of the building facing west, the other, east. When it # was high noon Banner time, it was 11 a.m. Tennessean time." # # Seigenthaler J. For 100 years, Tennessean had it covered. # The Tennessean 2007-05-11, republished 2015-04-06. # https://www.tennessean.com/story/insider/extras/2015/04/06/archives-seigenthaler-for-100-years-the-tennessean-had-it-covered/25348545/ # Rule NAME FROM TO - IN ON AT SAVE LETTER Rule Chicago 1920 only - Jun 13 2:00 1:00 D Rule Chicago 1920 1921 - Oct lastSun 2:00 0 S Rule Chicago 1921 only - Mar lastSun 2:00 1:00 D Rule Chicago 1922 1966 - Apr lastSun 2:00 1:00 D Rule Chicago 1922 1954 - Sep lastSun 2:00 0 S Rule Chicago 1955 1966 - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Chicago -5:50:36 - LMT 1883 Nov 18 18:00u -6:00 US C%sT 1920 -6:00 Chicago C%sT 1936 Mar 1 2:00 -5:00 - EST 1936 Nov 15 2:00 -6:00 Chicago C%sT 1942 -6:00 US C%sT 1946 -6:00 Chicago C%sT 1967 -6:00 US C%sT # Oliver County, ND switched from mountain to central time on 1992-10-25. Zone America/North_Dakota/Center -6:45:12 - LMT 1883 Nov 18 19:00u -7:00 US M%sT 1992 Oct 25 2:00 -6:00 US C%sT # Morton County, ND, switched from mountain to central time on # 2003-10-26, except for the area around Mandan which was already central time. # See . # Officially this switch also included part of Sioux County, and # Jones, Mellette, and Todd Counties in South Dakota; # but in practice these other counties were already observing central time. # See . Zone America/North_Dakota/New_Salem -6:45:39 - LMT 1883 Nov 18 19:00u -7:00 US M%sT 2003 Oct 26 2:00 -6:00 US C%sT # From Josh Findley (2011-01-21): # ...it appears that Mercer County, North Dakota, changed from the # mountain time zone to the central time zone at the last transition from # daylight-saving to standard time (on Nov. 7, 2010): # https://www.gpo.gov/fdsys/pkg/FR-2010-09-29/html/2010-24376.htm # http://www.bismarcktribune.com/news/local/article_1eb1b588-c758-11df-b472-001cc4c03286.html # From Andy Lipscomb (2011-01-24): # ...according to the Census Bureau, the largest city is Beulah (although # it's commonly referred to as Beulah-Hazen, with Hazen being the next # largest city in Mercer County). Google Maps places Beulah's city hall # at 47° 15' 51" N, 101° 46' 40" W, which yields an offset of 6h47'07". Zone America/North_Dakota/Beulah -6:47:07 - LMT 1883 Nov 18 19:00u -7:00 US M%sT 2010 Nov 7 2:00 -6:00 US C%sT # US mountain time, represented by Denver # # Colorado, far western Kansas, Montana, western # Nebraska, Nevada border (Jackpot, Owyhee, and Mountain City), # New Mexico, southwestern North Dakota, # western South Dakota, far western Texas (El Paso County, Hudspeth County, # and Pine Springs and Nickel Creek in Culberson County), Utah, Wyoming # # From Paul Eggert (2018-10-25): # On 1921-03-04 federal law placed all of Texas into the central time zone. # However, El Paso ignored the law for decades and continued to observe # mountain time, on the grounds that that's what they had always done # and they weren't about to let the federal government tell them what to do. # Eventually the federal government gave in and changed the law on # 1970-04-10 to match what El Paso was actually doing. Although # that's slightly after our 1970 cutoff, there is no need to create a # separate zone for El Paso since they were ignoring the law anyway. See: # Long T. El Pasoans were time rebels, fought to stay in Mountain zone. # El Paso Times. 2018-10-24 06:40 -06. # https://www.elpasotimes.com/story/news/local/el-paso/2018/10/24/el-pasoans-were-time-rebels-fought-stay-mountain-zone/1744509002/ # # Rule NAME FROM TO - IN ON AT SAVE LETTER Rule Denver 1920 1921 - Mar lastSun 2:00 1:00 D Rule Denver 1920 only - Oct lastSun 2:00 0 S Rule Denver 1921 only - May 22 2:00 0 S Rule Denver 1965 1966 - Apr lastSun 2:00 1:00 D Rule Denver 1965 1966 - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Denver -6:59:56 - LMT 1883 Nov 18 19:00u -7:00 US M%sT 1920 -7:00 Denver M%sT 1942 -7:00 US M%sT 1946 -7:00 Denver M%sT 1967 -7:00 US M%sT # US Pacific time, represented by Los Angeles # # California, northern Idaho (Benewah, Bonner, Boundary, Clearwater, # Kootenai, Latah, Lewis, Nez Perce, and Shoshone counties, Idaho county # north of the Salmon River, and the towns of Burgdorf and Warren), # Nevada (except West Wendover), Oregon (except the northern ¾ of # Malheur county), and Washington # From Paul Eggert (2016-08-20): # In early February 1948, in response to California's electricity shortage, # PG&E changed power frequency from 60 to 59.5 Hz during daylight hours, # causing electric clocks to lose six minutes per day. (This did not change # legal time, and is not part of the data here.) See: # Ross SA. An energy crisis from the past: Northern California in 1948. # Working Paper No. 8, Institute of Governmental Studies, UC Berkeley, # 1973-11. https://escholarship.org/uc/item/8x22k30c # # In another measure to save electricity, DST was instituted from 1948-03-14 # at 02:01 to 1949-01-16 at 02:00, with the governor having the option to move # the fallback transition earlier. See pages 3-4 of: # http://clerk.assembly.ca.gov/sites/clerk.assembly.ca.gov/files/archive/Statutes/1948/48Vol1_Chapters.pdf # # In response: # # Governor Warren received a torrent of objecting mail, and it is not too much # to speculate that the objections to Daylight Saving Time were one important # factor in the defeat of the Dewey-Warren Presidential ticket in California. # -- Ross, p 25 # # On December 8 the governor exercised the option, setting the date to January 1 # (LA Times 1948-12-09). The transition time was 02:00 (LA Times 1949-01-01). # # Despite the controversy, in 1949 California voters approved Proposition 12, # which established DST from April's last Sunday at 01:00 until September's # last Sunday at 02:00. This was amended by 1962's Proposition 6, which changed # the fall-back date to October's last Sunday. See: # https://repository.uchastings.edu/cgi/viewcontent.cgi?article=1501&context=ca_ballot_props # https://repository.uchastings.edu/cgi/viewcontent.cgi?article=1636&context=ca_ballot_props # # Rule NAME FROM TO - IN ON AT SAVE LETTER Rule CA 1948 only - Mar 14 2:01 1:00 D Rule CA 1949 only - Jan 1 2:00 0 S Rule CA 1950 1966 - Apr lastSun 1:00 1:00 D Rule CA 1950 1961 - Sep lastSun 2:00 0 S Rule CA 1962 1966 - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 20:00u -8:00 US P%sT 1946 -8:00 CA P%sT 1967 -8:00 US P%sT # Alaska # AK%sT is the modern abbreviation for -09 per USNO. # # From Paul Eggert (2017-06-15): # Howse writes that Alaska switched from the Julian to the Gregorian calendar, # and from east-of-GMT to west-of-GMT days, when the US bought it from Russia. # On Friday, 1867-10-18 (Gregorian), at precisely 15:30 local time, the # Russian forts and fleet at Sitka fired salutes to mark the ceremony of # formal transfer. See the Sacramento Daily Union (1867-11-14), p 3, col 2. # https://cdnc.ucr.edu/cgi-bin/cdnc?a=d&d=SDU18671114.2.12.1 # Sitka workers did not change their calendars until Sunday, 1867-10-20, # and so celebrated two Sundays that week. See: Ahllund T (tr Hallamaa P). # From the memoirs of a Finnish workman. Alaska History. 2006 Fall;21(2):1-25. # http://alaskahistoricalsociety.org/wp-content/uploads/2016/12/Ahllund-2006-Memoirs-of-a-Finnish-Workman.pdf # Include only the time zone part of this transition, ignoring the switch # from Julian to Gregorian, since we can't represent the Julian calendar. # # As far as we know, of the locations mentioned below only Sitka was # permanently inhabited in 1867 by anyone using either calendar. # (Yakutat was colonized by the Russians in 1799, but the settlement was # destroyed in 1805 by a Yakutat-kon war party.) Many of Alaska's inhabitants # were unaware of the US acquisition of Alaska, much less of any calendar or # time change. However, the Russian-influenced part of Alaska did observe # Russian time, and it is more accurate to model this than to ignore it. # The database format requires an exact transition time; use the Russian # salute as a somewhat-arbitrary time for the formal transfer of control for # all of Alaska. Sitka's UTC offset is -9:01:13; adjust its 15:30 to the # local times of other Alaskan locations so that they change simultaneously. # From Paul Eggert (2014-07-18): # One opinion of the early 1980s turmoil in Alaska over time zones and # daylight saving time appeared as graffiti on a Juneau airport wall: # "Welcome to Juneau. Please turn your watch back to the 19th century." # See: Turner W. Alaska's four time zones now two. NY Times 1983-11-01. # http://www.nytimes.com/1983/11/01/us/alaska-s-four-time-zones-now-two.html # # Steve Ferguson (2011-01-31) referred to the following source: # Norris F. Keeping time in Alaska: national directives, local response. # Alaska History 2001;16(1-2). # http://alaskahistoricalsociety.org/discover-alaska/glimpses-of-the-past/keeping-time-in-alaska/ # From Arthur David Olson (2011-02-01): # Here's database-relevant material from the 2001 "Alaska History" article: # # On September 20 [1979]...DOT...officials decreed that on April 27, # 1980, Juneau and other nearby communities would move to Yukon Time. # Sitka, Petersburg, Wrangell, and Ketchikan, however, would remain on # Pacific Time. # # ...on September 22, 1980, DOT Secretary Neil E. Goldschmidt rescinded the # Department's September 1979 decision. Juneau and other communities in # northern Southeast reverted to Pacific Time on October 26. # # On October 28 [1983]...the Metlakatla Indian Community Council voted # unanimously to keep the reservation on Pacific Time. # # According to DOT official Joanne Petrie, Indian reservations are not # bound to follow time zones imposed by neighboring jurisdictions. # # (The last is consistent with how the database now handles the Navajo # Nation.) # From Arthur David Olson (2011-02-09): # I just spoke by phone with a staff member at the Metlakatla Indian # Community office (using contact information available at # http://www.commerce.state.ak.us/dca/commdb/CIS.cfm?Comm_Boro_name=Metlakatla # It's shortly after 1:00 here on the east coast of the United States; # the staffer said it was shortly after 10:00 there. When I asked whether # that meant they were on Pacific time, they said no - they were on their # own time. I asked about daylight saving; they said it wasn't used. I # did not inquire about practices in the past. # From Arthur David Olson (2011-08-17): # For lack of better information, assume that Metlakatla's # abandonment of use of daylight saving resulted from the 1983 vote. # From Steffen Thorsen (2015-11-09): # It seems Metlakatla did go off PST on Sunday, November 1, changing # their time to AKST and are going to follow Alaska's DST, switching # between AKST and AKDT from now on.... # https://www.krbd.org/2015/10/30/annette-island-times-they-are-a-changing/ # From Ryan Stanley (2018-11-06): # The Metlakatla community in Alaska has decided not to change its # clock back an hour starting on November 4th, 2018 (day before yesterday). # They will be gmtoff=-28800 year-round. # https://www.facebook.com/141055983004923/photos/pb.141055983004923.-2207520000.1541465673./569081370202380/ # From Paul Eggert (2018-12-16): # In a 2018-12-11 special election, Metlakatla voted to go back to # Alaska time (including daylight saving time) starting next year. # https://www.krbd.org/2018/12/12/metlakatla-to-follow-alaska-standard-time-allow-liquor-sales/ # # From Ryan Stanley (2019-01-11): # The community will be changing back on the 20th of this month... # From Tim Parenti (2019-01-11): # Per an announcement on the Metlakatla community's official Facebook page, the # "fall back" will be on Sunday 2019-01-20 at 02:00: # https://www.facebook.com/141055983004923/photos/607150969728753/ # So they won't be waiting for Alaska to join them on 2019-03-10, but will # rather change their clocks twice in seven weeks. # From Paul Eggert (2023-01-23): # America/Adak is for the Aleutian Islands that are part of Alaska # and are west of 169.5° W. # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Juneau 15:02:19 - LMT 1867 Oct 19 15:33:32 -8:57:41 - LMT 1900 Aug 20 12:00 -8:00 - PST 1942 -8:00 US P%sT 1946 -8:00 - PST 1969 -8:00 US P%sT 1980 Apr 27 2:00 -9:00 US Y%sT 1980 Oct 26 2:00 -8:00 US P%sT 1983 Oct 30 2:00 -9:00 US Y%sT 1983 Nov 30 -9:00 US AK%sT Zone America/Sitka 14:58:47 - LMT 1867 Oct 19 15:30 -9:01:13 - LMT 1900 Aug 20 12:00 -8:00 - PST 1942 -8:00 US P%sT 1946 -8:00 - PST 1969 -8:00 US P%sT 1983 Oct 30 2:00 -9:00 US Y%sT 1983 Nov 30 -9:00 US AK%sT Zone America/Metlakatla 15:13:42 - LMT 1867 Oct 19 15:44:55 -8:46:18 - LMT 1900 Aug 20 12:00 -8:00 - PST 1942 -8:00 US P%sT 1946 -8:00 - PST 1969 -8:00 US P%sT 1983 Oct 30 2:00 -8:00 - PST 2015 Nov 1 2:00 -9:00 US AK%sT 2018 Nov 4 2:00 -8:00 - PST 2019 Jan 20 2:00 -9:00 US AK%sT Zone America/Yakutat 14:41:05 - LMT 1867 Oct 19 15:12:18 -9:18:55 - LMT 1900 Aug 20 12:00 -9:00 - YST 1942 -9:00 US Y%sT 1946 -9:00 - YST 1969 -9:00 US Y%sT 1983 Nov 30 -9:00 US AK%sT Zone America/Anchorage 14:00:24 - LMT 1867 Oct 19 14:31:37 -9:59:36 - LMT 1900 Aug 20 12:00 -10:00 - AST 1942 -10:00 US A%sT 1967 Apr -10:00 - AHST 1969 -10:00 US AH%sT 1983 Oct 30 2:00 -9:00 US Y%sT 1983 Nov 30 -9:00 US AK%sT Zone America/Nome 12:58:22 - LMT 1867 Oct 19 13:29:35 -11:01:38 - LMT 1900 Aug 20 12:00 -11:00 - NST 1942 -11:00 US N%sT 1946 -11:00 - NST 1967 Apr -11:00 - BST 1969 -11:00 US B%sT 1983 Oct 30 2:00 -9:00 US Y%sT 1983 Nov 30 -9:00 US AK%sT Zone America/Adak 12:13:22 - LMT 1867 Oct 19 12:44:35 -11:46:38 - LMT 1900 Aug 20 12:00 -11:00 - NST 1942 -11:00 US N%sT 1946 -11:00 - NST 1967 Apr -11:00 - BST 1969 -11:00 US B%sT 1983 Oct 30 2:00 -10:00 US AH%sT 1983 Nov 30 -10:00 US H%sT # The following switches don't make our 1970 cutoff. # # Kiska observed Tokyo date and time during Japanese occupation from # 1942-06-06 to 1943-07-29, and similarly for Attu from 1942-06-07 to # 1943-05-29 (all dates American). Both islands are now uninhabited. # # Shanks writes that part of southwest Alaska (e.g. Aniak) # switched from -11:00 to -10:00 on 1968-09-22 at 02:00, # and another part (e.g. Akiak) made the same switch five weeks later. # # From David Flater (2004-11-09): # In e-mail, 2004-11-02, Ray Hudson, historian/liaison to the Unalaska # Historic Preservation Commission, provided this information, which # suggests that Unalaska deviated from statutory time from early 1967 # possibly until 1983: # # Minutes of the Unalaska City Council Meeting, January 10, 1967: # "Except for St. Paul and Akutan, Unalaska is the only important # location not on Alaska Standard Time. The following resolution was # made by William Robinson and seconded by Henry Swanson: Be it # resolved that the City of Unalaska hereby goes to Alaska Standard # Time as of midnight Friday, January 13, 1967 (1 A.M. Saturday, # January 14, Alaska Standard Time.) This resolution was passed with # three votes for and one against." # Hawaii # From Arthur David Olson (2010-12-09): # "Hawaiian Time" by Robert C. Schmitt and Doak C. Cox appears on pages 207-225 # of volume 26 of The Hawaiian Journal of History (1992). As of 2010-12-09, # the article is available at # https://evols.library.manoa.hawaii.edu/bitstream/10524/239/2/JL26215.pdf # and indicates that standard time was adopted effective noon, January # 13, 1896 (page 218), that in "1933, the Legislature decreed daylight # saving for the period between the last Sunday of each April and the # last Sunday of each September, but less than a month later repealed the # act," (page 220), that year-round daylight saving time was in effect # from 1942-02-09 to 1945-09-30 (page 221, with no time of day given for # when clocks changed) and that clocks were changed by 30 minutes # effective the second Sunday of June, 1947 (page 219, with no time of # day given for when clocks changed). A footnote for the 1933 changes # cites Session Laws of Hawaii 1933, "Act. 90 (approved 26 Apr. 1933) # and Act 163 (approved 21 May 1933)." # From Arthur David Olson (2011-01-19): # The following is from "Laws of the Territory of Hawaii Passed by the # Seventeenth Legislature: Regular Session 1933," available (as of # 2011-01-19) at American University's Pence Law Library. Page 85: "Act # 90...At 2 o'clock ante meridian of the last Sunday in April of each # year, the standard time of this Territory shall be advanced one # hour...This Act shall take effect upon its approval. Approved this 26th # day of April, A. D. 1933. LAWRENCE M JUDD, Governor of the Territory of # Hawaii." Page 172: "Act 163...Act 90 of the Session Laws of 1933 is # hereby repealed...This Act shall take effect upon its approval, upon # which date the standard time of this Territory shall be restored to # that existing immediately prior to the taking effect of said Act 90. # Approved this 21st day of May, A. D. 1933. LAWRENCE M. JUDD, Governor # of the Territory of Hawaii." # # Note that 1933-05-21 was a Sunday. # We're left to guess the time of day when Act 163 was approved; guess noon. # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone Pacific/Honolulu -10:31:26 - LMT 1896 Jan 13 12:00 -10:30 - HST 1933 Apr 30 2:00 -10:30 1:00 HDT 1933 May 21 12:00 -10:30 US H%sT 1947 Jun 8 2:00 -10:00 - HST # Now we turn to US areas that have diverged from the consensus since 1970. # Arizona mostly uses MST. # From Paul Eggert (2002-10-20): # # The information in the rest of this paragraph is derived from the # Daylight Saving Time web page # (2002-01-23) # maintained by the Arizona State Library, Archives and Public Records. # Between 1944-01-01 and 1944-04-01 the State of Arizona used standard # time, but by federal law railroads, airlines, bus lines, military # personnel, and some engaged in interstate commerce continued to # observe war (i.e., daylight saving) time. The 1944-03-17 Phoenix # Gazette says that was the date the law changed, and that 04-01 was # the date the state's clocks would change. In 1945 the State of # Arizona used standard time all year, again with exceptions only as # mandated by federal law. Arizona observed DST in 1967, but Arizona # Laws 1968, ch. 183 (effective 1968-03-21) repealed DST. # # Shanks says the 1944 experiment came to an end on 1944-03-17. # Go with the Arizona State Library instead. # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Phoenix -7:28:18 - LMT 1883 Nov 18 19:00u -7:00 US M%sT 1944 Jan 1 0:01 -7:00 - MST 1944 Apr 1 0:01 -7:00 US M%sT 1944 Oct 1 0:01 -7:00 - MST 1967 -7:00 US M%sT 1968 Mar 21 -7:00 - MST # From Arthur David Olson (1988-02-13): # A writer from the Inter Tribal Council of Arizona, Inc., # notes in private correspondence dated 1987-12-28 that "Presently, only the # Navajo Nation participates in the Daylight Saving Time policy, due to its # large size and location in three states." (The "only" means that other # tribal nations don't use DST.) # # From Paul Eggert (2013-08-26): # See America/Denver for a zone appropriate for the Navajo Nation. # Southern Idaho (Ada, Adams, Bannock, Bear Lake, Bingham, Blaine, # Boise, Bonneville, Butte, Camas, Canyon, Caribou, Cassia, Clark, # Custer, Elmore, Franklin, Fremont, Gem, Gooding, Jefferson, Jerome, # Lemhi, Lincoln, Madison, Minidoka, Oneida, Owyhee, Payette, Power, # Teton, Twin Falls, Valley, Washington counties, and the southern # quarter of Idaho county) and eastern Oregon (most of Malheur County) # switched four weeks late in 1974. # # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Boise -7:44:49 - LMT 1883 Nov 18 20:00u -8:00 US P%sT 1923 May 13 2:00 -7:00 US M%sT 1974 -7:00 - MST 1974 Feb 3 2:00 -7:00 US M%sT # Indiana # # For a map of Indiana's time zone regions, see: # https://en.wikipedia.org/wiki/Time_in_Indiana # # From Paul Eggert (2018-11-30): # A brief but entertaining history of time in Indiana describes a 1949 debate # in the Indiana House where city legislators (who favored "fast time") # tussled with farm legislators (who didn't) over a bill to outlaw DST: # "Lacking enough votes, the city faction tries to filibuster until time runs # out on the session at midnight, but rural champion Rep. Herbert Copeland, # R-Madison, leans over the gallery railing and forces the official clock # back to 9 p.m., breaking it in the process. The clock sticks on 9 as the # debate rages on into the night. The filibuster finally dies out and the # bill passes, while outside the chamber, clocks read 3:30 a.m. In the end, # it doesn't matter which side won. The law has no enforcement powers and # is simply ignored by fast-time communities." # How Indiana went from 'God's time' to split zones and daylight-saving. # Indianapolis Star. 2018-11-27 14:58 -05. # https://www.indystar.com/story/news/politics/2018/11/27/indianapolis-indiana-time-zone-history-central-eastern-daylight-savings-time/2126300002/ # # From Paul Eggert (2007-08-17): # Since 1970, most of Indiana has been like America/Indiana/Indianapolis, # with the following exceptions: # # - Gibson, Jasper, Lake, LaPorte, Newton, Porter, Posey, Spencer, # Vanderburgh, and Warrick counties have been like America/Chicago. # # - Dearborn and Ohio counties have been like America/New_York. # # - Clark, Floyd, and Harrison counties have been like # America/Kentucky/Louisville. # # - Crawford, Daviess, Dubois, Knox, Martin, Perry, Pike, Pulaski, Starke, # and Switzerland counties have their own time zone histories as noted below. # # Shanks partitioned Indiana into 345 regions, each with its own time history, # and wrote "Even newspaper reports present contradictory information." # Those Hoosiers! Such a flighty and changeable people! # Fortunately, most of the complexity occurred before our cutoff date of 1970. # # Other than Indianapolis, the Indiana place names are so nondescript # that they would be ambiguous if we left them at the 'America' level. # So we reluctantly put them all in a subdirectory 'America/Indiana'. # From Paul Eggert (2014-06-26): # https://www.federalregister.gov/articles/2006/01/20/06-563/standard-time-zone-boundary-in-the-state-of-indiana # says "DOT is relocating the time zone boundary in Indiana to move Starke, # Pulaski, Knox, Daviess, Martin, Pike, Dubois, and Perry Counties from the # Eastern Time Zone to the Central Time Zone.... The effective date of # this rule is 2 a.m. EST Sunday, April 2, 2006, which is the # changeover date from standard time to Daylight Saving Time." # Strictly speaking, this meant the affected counties changed their # clocks twice that night, but this obviously was in error. The intent # was that 01:59:59 EST be followed by 02:00:00 CDT. # From Gwillim Law (2007-02-10): # The Associated Press has been reporting that Pulaski County, Indiana is # going to switch from Central to Eastern Time on March 11, 2007.... # http://www.indystar.com/apps/pbcs.dll/article?AID=/20070207/LOCAL190108/702070524/0/LOCAL # Rule NAME FROM TO - IN ON AT SAVE LETTER Rule Indianapolis 1941 only - Jun 22 2:00 1:00 D Rule Indianapolis 1941 1954 - Sep lastSun 2:00 0 S Rule Indianapolis 1946 1954 - Apr lastSun 2:00 1:00 D # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Indiana/Indianapolis -5:44:38 - LMT 1883 Nov 18 18:00u -6:00 US C%sT 1920 -6:00 Indianapolis C%sT 1942 -6:00 US C%sT 1946 -6:00 Indianapolis C%sT 1955 Apr 24 2:00 -5:00 - EST 1957 Sep 29 2:00 -6:00 - CST 1958 Apr 27 2:00 -5:00 - EST 1969 -5:00 US E%sT 1971 -5:00 - EST 2006 -5:00 US E%sT # # Eastern Crawford County, Indiana, left its clocks alone in 1974, # as well as from 1976 through 2005. # Rule NAME FROM TO - IN ON AT SAVE LETTER Rule Marengo 1951 only - Apr lastSun 2:00 1:00 D Rule Marengo 1951 only - Sep lastSun 2:00 0 S Rule Marengo 1954 1960 - Apr lastSun 2:00 1:00 D Rule Marengo 1954 1960 - Sep lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Indiana/Marengo -5:45:23 - LMT 1883 Nov 18 18:00u -6:00 US C%sT 1951 -6:00 Marengo C%sT 1961 Apr 30 2:00 -5:00 - EST 1969 -5:00 US E%sT 1974 Jan 6 2:00 -6:00 1:00 CDT 1974 Oct 27 2:00 -5:00 US E%sT 1976 -5:00 - EST 2006 -5:00 US E%sT # # Daviess, Dubois, Knox, and Martin Counties, Indiana, # switched from eastern to central time in April 2006, then switched back # in November 2007. # Rule NAME FROM TO - IN ON AT SAVE LETTER Rule Vincennes 1946 only - Apr lastSun 2:00 1:00 D Rule Vincennes 1946 only - Sep lastSun 2:00 0 S Rule Vincennes 1953 1954 - Apr lastSun 2:00 1:00 D Rule Vincennes 1953 1959 - Sep lastSun 2:00 0 S Rule Vincennes 1955 only - May 1 0:00 1:00 D Rule Vincennes 1956 1963 - Apr lastSun 2:00 1:00 D Rule Vincennes 1960 only - Oct lastSun 2:00 0 S Rule Vincennes 1961 only - Sep lastSun 2:00 0 S Rule Vincennes 1962 1963 - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Indiana/Vincennes -5:50:07 - LMT 1883 Nov 18 18:00u -6:00 US C%sT 1946 -6:00 Vincennes C%sT 1964 Apr 26 2:00 -5:00 - EST 1969 -5:00 US E%sT 1971 -5:00 - EST 2006 Apr 2 2:00 -6:00 US C%sT 2007 Nov 4 2:00 -5:00 US E%sT # # Perry County, Indiana, switched from eastern to central time in April 2006. # From Alois Treindl (2019-07-09): # The Indianapolis News, Friday 27 October 1967 states that Perry County # returned to CST. It went again to EST on 27 April 1969, as documented by the # Indianapolis star of Saturday 26 April. # Rule NAME FROM TO - IN ON AT SAVE LETTER Rule Perry 1955 only - May 1 0:00 1:00 D Rule Perry 1955 1960 - Sep lastSun 2:00 0 S Rule Perry 1956 1963 - Apr lastSun 2:00 1:00 D Rule Perry 1961 1963 - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Indiana/Tell_City -5:47:03 - LMT 1883 Nov 18 18:00u -6:00 US C%sT 1946 -6:00 Perry C%sT 1964 Apr 26 2:00 -5:00 - EST 1967 Oct 29 2:00 -6:00 US C%sT 1969 Apr 27 2:00 -5:00 US E%sT 1971 -5:00 - EST 2006 Apr 2 2:00 -6:00 US C%sT # # Pike County, Indiana moved from central to eastern time in 1977, # then switched back in 2006, then switched back again in 2007. # Rule NAME FROM TO - IN ON AT SAVE LETTER Rule Pike 1955 only - May 1 0:00 1:00 D Rule Pike 1955 1960 - Sep lastSun 2:00 0 S Rule Pike 1956 1964 - Apr lastSun 2:00 1:00 D Rule Pike 1961 1964 - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Indiana/Petersburg -5:49:07 - LMT 1883 Nov 18 18:00u -6:00 US C%sT 1955 -6:00 Pike C%sT 1965 Apr 25 2:00 -5:00 - EST 1966 Oct 30 2:00 -6:00 US C%sT 1977 Oct 30 2:00 -5:00 - EST 2006 Apr 2 2:00 -6:00 US C%sT 2007 Nov 4 2:00 -5:00 US E%sT # # Starke County, Indiana moved from central to eastern time in 1991, # then switched back in 2006. # From Arthur David Olson (1991-10-28): # An article on page A3 of the Sunday, 1991-10-27 Washington Post # notes that Starke County switched from Central time to Eastern time as of # 1991-10-27. # Rule NAME FROM TO - IN ON AT SAVE LETTER Rule Starke 1947 1961 - Apr lastSun 2:00 1:00 D Rule Starke 1947 1954 - Sep lastSun 2:00 0 S Rule Starke 1955 1956 - Oct lastSun 2:00 0 S Rule Starke 1957 1958 - Sep lastSun 2:00 0 S Rule Starke 1959 1961 - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Indiana/Knox -5:46:30 - LMT 1883 Nov 18 18:00u -6:00 US C%sT 1947 -6:00 Starke C%sT 1962 Apr 29 2:00 -5:00 - EST 1963 Oct 27 2:00 -6:00 US C%sT 1991 Oct 27 2:00 -5:00 - EST 2006 Apr 2 2:00 -6:00 US C%sT # # Pulaski County, Indiana, switched from eastern to central time in # April 2006 and then switched back in March 2007. # Rule NAME FROM TO - IN ON AT SAVE LETTER Rule Pulaski 1946 1960 - Apr lastSun 2:00 1:00 D Rule Pulaski 1946 1954 - Sep lastSun 2:00 0 S Rule Pulaski 1955 1956 - Oct lastSun 2:00 0 S Rule Pulaski 1957 1960 - Sep lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Indiana/Winamac -5:46:25 - LMT 1883 Nov 18 18:00u -6:00 US C%sT 1946 -6:00 Pulaski C%sT 1961 Apr 30 2:00 -5:00 - EST 1969 -5:00 US E%sT 1971 -5:00 - EST 2006 Apr 2 2:00 -6:00 US C%sT 2007 Mar 11 2:00 -5:00 US E%sT # # Switzerland County, Indiana, did not observe DST from 1973 through 2005. # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Indiana/Vevay -5:40:16 - LMT 1883 Nov 18 18:00u -6:00 US C%sT 1954 Apr 25 2:00 -5:00 - EST 1969 -5:00 US E%sT 1973 -5:00 - EST 2006 -5:00 US E%sT # From Paul Eggert (2018-03-20): # The Louisville & Nashville Railroad's 1883-11-18 change occurred at # 10:00 old local time; train were supposed to come to a standstill # for precisely 18 minutes. See Bartky Fig. 1 (page 50). It is not # clear how this matched civil time in Louisville, so for now continue # to assume Louisville switched at noon new local time, like New York. # # From Michael Deckers (2019-08-06): # From the contemporary source given by Alois Treindl, # the switch in Louisville on 1946-04-28 was on 00:01 # From Paul Eggert (2019-08-26): # That source was the Louisville Courier-Journal, 1946-04-27, p 4. # Shanks gives 02:00 for all 20th-century transition times in Louisville. # Evidently this is wrong for spring 1946. Although also likely wrong # for other dates, we have no data. # # Part of Kentucky left its clocks alone in 1974. # This also includes Clark, Floyd, and Harrison counties in Indiana. # Rule NAME FROM TO - IN ON AT SAVE LETTER Rule Louisville 1921 only - May 1 2:00 1:00 D Rule Louisville 1921 only - Sep 1 2:00 0 S Rule Louisville 1941 only - Apr lastSun 2:00 1:00 D Rule Louisville 1941 only - Sep lastSun 2:00 0 S Rule Louisville 1946 only - Apr lastSun 0:01 1:00 D Rule Louisville 1946 only - Jun 2 2:00 0 S Rule Louisville 1950 1961 - Apr lastSun 2:00 1:00 D Rule Louisville 1950 1955 - Sep lastSun 2:00 0 S Rule Louisville 1956 1961 - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Kentucky/Louisville -5:43:02 - LMT 1883 Nov 18 18:00u -6:00 US C%sT 1921 -6:00 Louisville C%sT 1942 -6:00 US C%sT 1946 -6:00 Louisville C%sT 1961 Jul 23 2:00 -5:00 - EST 1968 -5:00 US E%sT 1974 Jan 6 2:00 -6:00 1:00 CDT 1974 Oct 27 2:00 -5:00 US E%sT # # Wayne County, Kentucky # # From Lake Cumberland LIFE # http://www.lake-cumberland.com/life/archive/news990129time.shtml # (1999-01-29) via WKYM-101.7: # Clinton County has joined Wayne County in asking the DoT to change from # the Central to the Eastern time zone.... The Wayne County government made # the same request in December. And while Russell County officials have not # taken action, the majority of respondents to a poll conducted there in # August indicated they would like to change to "fast time" also. # The three Lake Cumberland counties are the farthest east of any U.S. # location in the Central time zone. # # From Rich Wales (2000-08-29): # After prolonged debate, and despite continuing deep differences of opinion, # Wayne County (central Kentucky) is switching from Central (-0600) to Eastern # (-0500) time. They won't "fall back" this year. See Sara Shipley, # The difference an hour makes, Nando Times (2000-08-29 15:33 -0400). # # From Paul Eggert (2001-07-16): # The final rule was published in the # Federal Register 65, 160 (2000-08-17), pp 50154-50158. # https://www.gpo.gov/fdsys/pkg/FR-2000-08-17/html/00-20854.htm # Zone America/Kentucky/Monticello -5:39:24 - LMT 1883 Nov 18 18:00u -6:00 US C%sT 1946 -6:00 - CST 1968 -6:00 US C%sT 2000 Oct 29 2:00 -5:00 US E%sT # From Rives McDow (2000-08-30): # Here ... are all the changes in the US since 1985. # Kearny County, KS (put all of county on central; # previously split between MST and CST) ... 1990-10 # Starke County, IN (from CST to EST) ... 1991-10 # Oliver County, ND (from MST to CST) ... 1992-10 # West Wendover, NV (from PST TO MST) ... 1999-10 # Wayne County, KY (from CST to EST) ... 2000-10 # # From Paul Eggert (2001-07-17): # We don't know where the line used to be within Kearny County, KS, # so omit that change for now. # See America/Indiana/Knox for the Starke County, IN change. # See America/North_Dakota/Center for the Oliver County, ND change. # West Wendover, NV officially switched from Pacific to mountain time on # 1999-10-31. See the # Federal Register 64, 203 (1999-10-21), pp 56705-56707. # https://www.gpo.gov/fdsys/pkg/FR-1999-10-21/html/99-27240.htm # However, the Federal Register says that West Wendover already operated # on mountain time, and the rule merely made this official; # hence a separate tz entry is not needed. # Michigan # # From Bob Devine (1988-01-28): # Michigan didn't observe DST from 1968 to 1973. # # From Paul Eggert (1999-03-31): # Shanks writes that Michigan started using standard time on 1885-09-18, # but Howse writes (pp 124-125, referring to Popular Astronomy, 1901-01) # that Detroit kept # # local time until 1900 when the City Council decreed that clocks should # be put back twenty-eight minutes to Central Standard Time. Half the # city obeyed, half refused. After considerable debate, the decision # was rescinded and the city reverted to Sun time. A derisive offer to # erect a sundial in front of the city hall was referred to the # Committee on Sewers. Then, in 1905, Central time was adopted # by city vote. # # This story is too entertaining to be false, so go with Howse over Shanks. # # From Paul Eggert (2001-03-06): # Garland (1927) writes "Cleveland and Detroit advanced their clocks # one hour in 1914." This change is not in Shanks. We have no more # info, so omit this for now. # # From Paul Eggert (2019-07-06): # Due to a complicated set of legal maneuvers, in 1967 Michigan did # not start daylight saving time when the rest of the US did. # Instead, it began DST on Jun 14 at 00:01. This was big news: # the Detroit Free Press reported it at the top of Page 1 on # 1967-06-14, in an article "State Adjusting to Switch to Fast Time" # by Gary Blonston, above an article about Thurgood Marshall's # confirmation to the US Supreme Court. Although Shanks says Detroit # observed DST until 1967-10-29 00:01, that time of day seems to be # incorrect, as the Free Press later said DST ended in Michigan at the # same time as the rest of the US. Also, although Shanks reports no DST in # Detroit in 1968, it did observe DST that year; in the November 1968 # election Michigan voters narrowly repealed DST, effective 1969. # # Most of Michigan observed DST from 1973 on, but was a bit late in 1975. # Rule NAME FROM TO - IN ON AT SAVE LETTER Rule Detroit 1948 only - Apr lastSun 2:00 1:00 D Rule Detroit 1948 only - Sep lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Detroit -5:32:11 - LMT 1905 -6:00 - CST 1915 May 15 2:00 -5:00 - EST 1942 -5:00 US E%sT 1946 -5:00 Detroit E%sT 1967 Jun 14 0:01 -5:00 US E%sT 1969 -5:00 - EST 1973 -5:00 US E%sT 1975 -5:00 - EST 1975 Apr 27 2:00 -5:00 US E%sT # # Dickinson, Gogebic, Iron, and Menominee Counties, Michigan, # switched from EST to CST/CDT in 1973. # Rule NAME FROM TO - IN ON AT SAVE LETTER Rule Menominee 1946 only - Apr lastSun 2:00 1:00 D Rule Menominee 1946 only - Sep lastSun 2:00 0 S Rule Menominee 1966 only - Apr lastSun 2:00 1:00 D Rule Menominee 1966 only - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Menominee -5:50:27 - LMT 1885 Sep 18 12:00 -6:00 US C%sT 1946 -6:00 Menominee C%sT 1969 Apr 27 2:00 -5:00 - EST 1973 Apr 29 2:00 -6:00 US C%sT # Navassa # administered by the US Fish and Wildlife Service # claimed by US under the provisions of the 1856 Guano Islands Act # also claimed by Haiti # occupied 1857/1900 by the Navassa Phosphate Co # US lighthouse 1917/1996-09 # currently uninhabited # see Mark Fineman, "An Isle Rich in Guano and Discord", # _Los Angeles Times_ (1998-11-10), A1, A10; it cites # Jimmy Skaggs, _The Great Guano Rush_ (1994). ################################################################################ # From Paul Eggert (2017-02-10): # # Unless otherwise specified, the source for data through 1990 is: # Thomas G. Shanks and Rique Pottenger, The International Atlas (6th edition), # San Diego: ACS Publications, Inc. (2003). # Unfortunately this book contains many errors and cites no sources. # # Many years ago Gwillim Law wrote that a good source # for time zone data was the International Air Transport # Association's Standard Schedules Information Manual (IATA SSIM), # published semiannually. Law sent in several helpful summaries # of the IATA's data after 1990. Except where otherwise noted, # IATA SSIM is the source for entries after 1990. # # Other sources occasionally used include: # # Milne J. Civil time. Geogr J. 1899 Feb;13(2):173-94 # . # # Pearce C. The Great Daylight Saving Time Controversy. # Australian Ebook Publisher. 2017. ISBN 978-1-925516-96-8. # # Edward W. Whitman, World Time Differences, # Whitman Publishing Co, 2 Niagara Av, Ealing, London (undated), # which I found in the UCLA library. # # William Willett, The Waste of Daylight, 19th edition # # [PDF] (1914-03) # # See the 'europe' file for Greenland. # Canada # From Alain LaBonté (1994-11-14): # I post here the time zone abbreviations standardized in Canada # for both English and French in the CAN/CSA-Z234.4-89 standard.... # # UTC Standard time Daylight saving time # offset French English French English # -2:30 - - HAT NDT # -3 - - HAA ADT # -3:30 HNT NST - - # -4 HNA AST HAE EDT # -5 HNE EST HAC CDT # -6 HNC CST HAR MDT # -7 HNR MST HAP PDT # -8 HNP PST HAY YDT # -9 HNY YST - - # # HN: Heure Normale ST: Standard Time # HA: Heure Avancée DT: Daylight saving Time # # A: de l'Atlantique Atlantic # C: du Centre Central # E: de l'Est Eastern # M: Mountain # N: Newfoundland # P: du Pacifique Pacific # R: des Rocheuses # T: de Terre-Neuve # Y: du Yukon Yukon # # From Paul Eggert (1994-11-22): # Alas, this sort of thing must be handled by localization software. # Unless otherwise specified, the data entries for Canada are all from Shanks # & Pottenger. # From Chris Walton (2006-04-01, 2006-04-25, 2006-06-26, 2007-01-31, # 2007-03-01): # The British Columbia government announced yesterday that it will # adjust daylight savings next year to align with changes in the # U.S. and the rest of Canada.... # https://archive.news.gov.bc.ca/releases/news_releases_2005-2009/2006AG0014-000330.htm # ... # Nova Scotia # Daylight saving time will be extended by four weeks starting in 2007.... # https://www.novascotia.ca/just/regulations/rg2/2006/ma1206.pdf # # [For New Brunswick] the new legislation dictates that the time change is to # be done at 02:00 instead of 00:01. # https://www.gnb.ca/0062/acts/BBA-2006/Chap-19.pdf # ... # Manitoba has traditionally changed the clock every fall at 03:00. # As of 2006, the transition is to take place one hour earlier at 02:00. # https://web2.gov.mb.ca/laws/statutes/ccsm/o030e.php # ... # [Alberta, Ontario, Quebec] will follow US rules. # http://www.qp.gov.ab.ca/documents/spring/CH03_06.CFM # http://www.e-laws.gov.on.ca/DBLaws/Source/Regs/English/2006/R06111_e.htm # http://www2.publicationsduquebec.gouv.qc.ca/dynamicSearch/telecharge.php?type=5&file=2006C39A.PDF # ... # P.E.I. will follow US rules.... # http://www.assembly.pe.ca/bills/pdf_chapter/62/3/chapter-41.pdf # ... # Province of Newfoundland and Labrador.... # http://www.hoa.gov.nl.ca/hoa/bills/Bill0634.htm # ... # Yukon # https://www.gov.yk.ca/legislation/regs/oic2006_127.pdf # ... # N.W.T. will follow US rules. Whoever maintains the government web site # does not seem to believe in bookmarks. To see the news release, click the # following link and search for "Daylight Savings Time Change". Press the # "Daylight Savings Time Change" link; it will fire off a popup using # JavaScript. # http://www.exec.gov.nt.ca/currentnews/currentPR.asp?mode=archive # ... # Nunavut # An amendment to the Interpretation Act was registered on February 19/2007.... # http://action.attavik.ca/home/justice-gn/attach/2007/gaz02part2.pdf # From Paul Eggert (2014-10-18): # H. David Matthews and Mary Vincent's map # "It's about TIME", _Canadian Geographic_ (September-October 1998) # http://www.canadiangeographic.ca/Magazine/SO98/alacarte.asp # contains detailed boundaries for regions observing nonstandard # time and daylight saving time arrangements in Canada circa 1998. # # National Research Council Canada maintains info about time zones and DST. # https://www.nrc-cnrc.gc.ca/eng/services/time/time_zones.html # https://www.nrc-cnrc.gc.ca/eng/services/time/faq/index.html#Q5 # Its unofficial information is often taken from Matthews and Vincent. # From Paul Eggert (2006-06-27): # For now, assume all of DST-observing Canada will fall into line with the # new US DST rules, # From Chris Walton (2011-12-01) # In the first of Tammy Hardwick's articles # http://www.ilovecreston.com/?p=articles&t=spec&ar=260 # she quotes the Friday November 1/1918 edition of the Creston Review. # The quote includes these two statements: # 'Sunday the CPR went back to the old system of time...' # '... The daylight saving scheme was dropped all over Canada at the same time,' # These statements refer to a transition from daylight time to standard time # that occurred nationally on Sunday October 27/1918. This transition was # also documented in the Saturday October 26/1918 edition of the Toronto Star. # In light of that evidence, we alter the date from the earlier believed # Oct 31, to Oct 27, 1918 (and Sunday is a more likely transition day # than Thursday) in all Canadian rulesets. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Canada 1918 only - Apr 14 2:00 1:00 D Rule Canada 1918 only - Oct 27 2:00 0 S Rule Canada 1942 only - Feb 9 2:00 1:00 W # War Rule Canada 1945 only - Aug 14 23:00u 1:00 P # Peace Rule Canada 1945 only - Sep 30 2:00 0 S Rule Canada 1974 1986 - Apr lastSun 2:00 1:00 D Rule Canada 1974 2006 - Oct lastSun 2:00 0 S Rule Canada 1987 2006 - Apr Sun>=1 2:00 1:00 D Rule Canada 2007 max - Mar Sun>=8 2:00 1:00 D Rule Canada 2007 max - Nov Sun>=1 2:00 0 S # Newfoundland and Labrador # From Paul Eggert (2017-10-14): # Legally Labrador should observe Newfoundland time; see: # McLeod J. Labrador time - legal or not? St. John's Telegram, 2017-10-07 # http://www.thetelegram.com/news/local/labrador-time--legal-or-not-154860/ # Matthews and Vincent (1998) write that the only part of Labrador # that follows the rules is the southeast corner, including Port Hope # Simpson and Mary's Harbour, but excluding, say, Black Tickle. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule StJohns 1917 only - Apr 8 2:00 1:00 D Rule StJohns 1917 only - Sep 17 2:00 0 S # Whitman gives 1919 Apr 5 and 1920 Apr 5; go with Shanks & Pottenger. Rule StJohns 1919 only - May 5 23:00 1:00 D Rule StJohns 1919 only - Aug 12 23:00 0 S # For 1931-1935 Whitman gives Apr same date; go with Shanks & Pottenger. Rule StJohns 1920 1935 - May Sun>=1 23:00 1:00 D Rule StJohns 1920 1935 - Oct lastSun 23:00 0 S # For 1936-1941 Whitman gives May Sun>=8 and Oct Sun>=1; go with Shanks & # Pottenger. Rule StJohns 1936 1941 - May Mon>=9 0:00 1:00 D Rule StJohns 1936 1941 - Oct Mon>=2 0:00 0 S # Whitman gives the following transitions: # 1942 03-01/12-31, 1943 05-30/09-05, 1944 07-10/09-02, 1945 01-01/10-07 # but go with Shanks & Pottenger and assume they used Canadian rules. # For 1946-9 Whitman gives May 5,4,9,1 - Oct 1,5,3,2, and for 1950 he gives # Apr 30 - Sep 24; go with Shanks & Pottenger. Rule StJohns 1946 1950 - May Sun>=8 2:00 1:00 D Rule StJohns 1946 1950 - Oct Sun>=2 2:00 0 S Rule StJohns 1951 1986 - Apr lastSun 2:00 1:00 D Rule StJohns 1951 1959 - Sep lastSun 2:00 0 S Rule StJohns 1960 1986 - Oct lastSun 2:00 0 S # From Paul Eggert (2000-10-02): # INMS (2000-09-12) says that, since 1988 at least, Newfoundland switches # at 00:01 local time. For now, assume it started in 1987. # From Michael Pelley (2011-09-12): # We received today, Monday, September 12, 2011, notification that the # changes to the Newfoundland Standard Time Act have been proclaimed. # The change in the Act stipulates that the change from Daylight Savings # Time to Standard Time and from Standard Time to Daylight Savings Time # now occurs at 2:00AM. # ... # http://www.assembly.nl.ca/legislation/sr/annualstatutes/2011/1106.chp.htm # ... # MICHAEL PELLEY | Manager of Enterprise Architecture - Solution Delivery # Office of the Chief Information Officer # Executive Council # Government of Newfoundland & Labrador Rule StJohns 1987 only - Apr Sun>=1 0:01 1:00 D Rule StJohns 1987 2006 - Oct lastSun 0:01 0 S Rule StJohns 1988 only - Apr Sun>=1 0:01 2:00 DD Rule StJohns 1989 2006 - Apr Sun>=1 0:01 1:00 D Rule StJohns 2007 2011 - Mar Sun>=8 0:01 1:00 D Rule StJohns 2007 2010 - Nov Sun>=1 0:01 0 S # # St John's has an apostrophe, but Posix file names can't have apostrophes. # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/St_Johns -3:30:52 - LMT 1884 -3:30:52 StJohns N%sT 1918 -3:30:52 Canada N%sT 1919 -3:30:52 StJohns N%sT 1935 Mar 30 -3:30 StJohns N%sT 1942 May 11 -3:30 Canada N%sT 1946 -3:30 StJohns N%sT 2011 Nov -3:30 Canada N%sT # most of east Labrador # The name 'Happy Valley-Goose Bay' is too long; use 'Goose Bay'. # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Goose_Bay -4:01:40 - LMT 1884 # Happy Valley-Goose Bay -3:30:52 - NST 1918 -3:30:52 Canada N%sT 1919 -3:30:52 - NST 1935 Mar 30 -3:30 - NST 1936 -3:30 StJohns N%sT 1942 May 11 -3:30 Canada N%sT 1946 -3:30 StJohns N%sT 1966 Mar 15 2:00 -4:00 StJohns A%sT 2011 Nov -4:00 Canada A%sT # west Labrador, Nova Scotia, Prince Edward I, # Îles-de-la-Madeleine, Listuguj reserve # From Brian Inglis (2015-07-20): # From the historical weather station records available at: # https://weatherspark.com/history/28351/1971/Sydney-Nova-Scotia-Canada # Sydney shares the same time history as Glace Bay, so was # likely to be the same across the island.... # Sydney, as the capital and most populous location, or Cape Breton, would # have been better names for the zone had we known this in 1996. # From Paul Eggert (2015-07-20): # Shanks & Pottenger write that since 1970 most of this region has been like # Halifax. Many locales did not observe peacetime DST until 1972; # the Cape Breton area, represented by Glace Bay, is the largest we know of # (Glace Bay was perhaps not the best name choice but no point changing now). # Shanks & Pottenger also write that Liverpool, NS was the only town # in Canada to observe DST in 1971 but not 1970; for now we'll assume # this is a typo. # From Jeffery Nichols (2020-01-09): # America/Halifax ... also applies to Îles-de-la-Madeleine and the Listuguj # reserve in Quebec. Officially, this came into effect on January 1, 2007 # (Legal Time Act, CQLR c T-5.1), but the legislative debates surrounding that # bill say that it is "accommodating the customs and practices" of those # regions, which suggests that they have always been in-line with Halifax. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Halifax 1916 only - Apr 1 0:00 1:00 D Rule Halifax 1916 only - Oct 1 0:00 0 S Rule Halifax 1920 only - May 9 0:00 1:00 D Rule Halifax 1920 only - Aug 29 0:00 0 S Rule Halifax 1921 only - May 6 0:00 1:00 D Rule Halifax 1921 1922 - Sep 5 0:00 0 S Rule Halifax 1922 only - Apr 30 0:00 1:00 D Rule Halifax 1923 1925 - May Sun>=1 0:00 1:00 D Rule Halifax 1923 only - Sep 4 0:00 0 S Rule Halifax 1924 only - Sep 15 0:00 0 S Rule Halifax 1925 only - Sep 28 0:00 0 S Rule Halifax 1926 only - May 16 0:00 1:00 D Rule Halifax 1926 only - Sep 13 0:00 0 S Rule Halifax 1927 only - May 1 0:00 1:00 D Rule Halifax 1927 only - Sep 26 0:00 0 S Rule Halifax 1928 1931 - May Sun>=8 0:00 1:00 D Rule Halifax 1928 only - Sep 9 0:00 0 S Rule Halifax 1929 only - Sep 3 0:00 0 S Rule Halifax 1930 only - Sep 15 0:00 0 S Rule Halifax 1931 1932 - Sep Mon>=24 0:00 0 S Rule Halifax 1932 only - May 1 0:00 1:00 D Rule Halifax 1933 only - Apr 30 0:00 1:00 D Rule Halifax 1933 only - Oct 2 0:00 0 S Rule Halifax 1934 only - May 20 0:00 1:00 D Rule Halifax 1934 only - Sep 16 0:00 0 S Rule Halifax 1935 only - Jun 2 0:00 1:00 D Rule Halifax 1935 only - Sep 30 0:00 0 S Rule Halifax 1936 only - Jun 1 0:00 1:00 D Rule Halifax 1936 only - Sep 14 0:00 0 S Rule Halifax 1937 1938 - May Sun>=1 0:00 1:00 D Rule Halifax 1937 1941 - Sep Mon>=24 0:00 0 S Rule Halifax 1939 only - May 28 0:00 1:00 D Rule Halifax 1940 1941 - May Sun>=1 0:00 1:00 D Rule Halifax 1946 1949 - Apr lastSun 2:00 1:00 D Rule Halifax 1946 1949 - Sep lastSun 2:00 0 S Rule Halifax 1951 1954 - Apr lastSun 2:00 1:00 D Rule Halifax 1951 1954 - Sep lastSun 2:00 0 S Rule Halifax 1956 1959 - Apr lastSun 2:00 1:00 D Rule Halifax 1956 1959 - Sep lastSun 2:00 0 S Rule Halifax 1962 1973 - Apr lastSun 2:00 1:00 D Rule Halifax 1962 1973 - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Halifax -4:14:24 - LMT 1902 Jun 15 -4:00 Halifax A%sT 1918 -4:00 Canada A%sT 1919 -4:00 Halifax A%sT 1942 Feb 9 2:00s -4:00 Canada A%sT 1946 -4:00 Halifax A%sT 1974 -4:00 Canada A%sT Zone America/Glace_Bay -3:59:48 - LMT 1902 Jun 15 -4:00 Canada A%sT 1953 -4:00 Halifax A%sT 1954 -4:00 - AST 1972 -4:00 Halifax A%sT 1974 -4:00 Canada A%sT # New Brunswick # From Paul Eggert (2007-01-31): # The Time Definition Act # says they changed at 00:01 through 2006, and # makes it # clear that this was the case since at least 1993. # For now, assume it started in 1993. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Moncton 1933 1935 - Jun Sun>=8 1:00 1:00 D Rule Moncton 1933 1935 - Sep Sun>=8 1:00 0 S Rule Moncton 1936 1938 - Jun Sun>=1 1:00 1:00 D Rule Moncton 1936 1938 - Sep Sun>=1 1:00 0 S Rule Moncton 1939 only - May 27 1:00 1:00 D Rule Moncton 1939 1941 - Sep Sat>=21 1:00 0 S Rule Moncton 1940 only - May 19 1:00 1:00 D Rule Moncton 1941 only - May 4 1:00 1:00 D Rule Moncton 1946 1972 - Apr lastSun 2:00 1:00 D Rule Moncton 1946 1956 - Sep lastSun 2:00 0 S Rule Moncton 1957 1972 - Oct lastSun 2:00 0 S Rule Moncton 1993 2006 - Apr Sun>=1 0:01 1:00 D Rule Moncton 1993 2006 - Oct lastSun 0:01 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Moncton -4:19:08 - LMT 1883 Dec 9 -5:00 - EST 1902 Jun 15 -4:00 Canada A%sT 1933 -4:00 Moncton A%sT 1942 -4:00 Canada A%sT 1946 -4:00 Moncton A%sT 1973 -4:00 Canada A%sT 1993 -4:00 Moncton A%sT 2007 -4:00 Canada A%sT # Quebec # From Paul Eggert (2020-01-10): # See America/Toronto for most of Quebec, including Montreal. # See America/Halifax for the Îles de la Madeleine and the Listuguj reserve. # See America/Puerto_Rico for east of Natashquan. # Ontario # From Mark Brader (2003-07-26): # [According to the Toronto Star] Orillia, Ontario, adopted DST # effective Saturday, 1912-06-22, 22:00; the article mentions that # Port Arthur (now part of Thunder Bay, Ontario) as well as Moose Jaw # have already done so. In Orillia DST was to run until Saturday, # 1912-08-31 (no time mentioned), but it was met with considerable # hostility from certain segments of the public, and was revoked after # only two weeks - I copied it as Saturday, 1912-07-07, 22:00, but # presumably that should be -07-06. (1912-06-19, -07-12; also letters # earlier in June). # # Kenora, Ontario, was to abandon DST on 1914-06-01 (-05-21). # # From Paul Eggert (2017-07-08): # For more on Orillia, see: Daubs K. Bold attempt at daylight saving # time became a comic failure in Orillia. Toronto Star 2017-07-08. # https://www.thestar.com/news/insight/2017/07/08/bold-attempt-at-daylight-saving-time-became-a-comic-failure-in-orillia.html # From Mark Brader (2010-03-06): # # In the (Toronto) Globe and Mail for Saturday, 1955-09-24, in the bottom # right corner of page 1, it says that Toronto will return to standard # time at 2 am Sunday morning (which agrees with the database), and that: # # The one-hour setback will go into effect throughout most of Ontario, # except in areas like Windsor which remains on standard time all year. # # ... I don't know if Windsor began observing DST when Detroit did, # or in 1974, or on some other date. # # By the way, the article continues by noting that: # # Some cities in the United States have pushed the deadline back # three weeks and will change over from daylight saving in October. # From Arthur David Olson (2010-07-17): # # "Standard Time and Time Zones in Canada" appeared in # The Journal of The Royal Astronomical Society of Canada, # volume 26, number 2 (February 1932) and, as of 2010-07-17, # was available at # http://adsabs.harvard.edu/full/1932JRASC..26...49S # # It includes the text below (starting on page 57): # # A list of the places in Canada using daylight saving time would # require yearly revision. From information kindly furnished by # the provincial governments and by the postmasters in many cities # and towns, it is found that the following places used daylight sav- # ing in 1930. The information for the province of Quebec is definite, # for the other provinces only approximate: # # Province Daylight saving time used # Prince Edward Island Not used. # Nova Scotia In Halifax only. # New Brunswick In St. John only. # Quebec In the following places: # Montreal Lachine # Quebec Mont-Royal # Lévis Iberville # St. Lambert Cap de la Madelèine # Verdun Loretteville # Westmount Richmond # Outremont St. Jérôme # Longueuil Greenfield Park # Arvida Waterloo # Chambly-Canton Beaulieu # Melbourne La Tuque # St. Théophile Buckingham # Ontario Used generally in the cities and towns along # the southerly part of the province. Not # used in the northwesterly part. # Manitoba Not used. # Saskatchewan In Regina only. # Alberta Not used. # British Columbia Not used. # # With some exceptions, the use of daylight saving may be said to be limited # to those cities and towns lying between Quebec city and Windsor, Ont. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Toronto 1919 only - Mar 30 23:30 1:00 D Rule Toronto 1919 only - Oct 26 0:00 0 S Rule Toronto 1920 only - May 2 2:00 1:00 D Rule Toronto 1920 only - Sep 26 0:00 0 S Rule Toronto 1921 only - May 15 2:00 1:00 D Rule Toronto 1921 only - Sep 15 2:00 0 S Rule Toronto 1922 1923 - May Sun>=8 2:00 1:00 D # Shanks & Pottenger say 1923-09-19; assume it's a typo and that "-16" # was meant. Rule Toronto 1922 1926 - Sep Sun>=15 2:00 0 S Rule Toronto 1924 1927 - May Sun>=1 2:00 1:00 D Rule Toronto 1927 1937 - Sep Sun>=25 2:00 0 S Rule Toronto 1928 1937 - Apr Sun>=25 2:00 1:00 D Rule Toronto 1938 1940 - Apr lastSun 2:00 1:00 D Rule Toronto 1938 1939 - Sep lastSun 2:00 0 S Rule Toronto 1945 1946 - Sep lastSun 2:00 0 S Rule Toronto 1946 only - Apr lastSun 2:00 1:00 D Rule Toronto 1947 1949 - Apr lastSun 0:00 1:00 D Rule Toronto 1947 1948 - Sep lastSun 0:00 0 S Rule Toronto 1949 only - Nov lastSun 0:00 0 S Rule Toronto 1950 1973 - Apr lastSun 2:00 1:00 D Rule Toronto 1950 only - Nov lastSun 2:00 0 S Rule Toronto 1951 1956 - Sep lastSun 2:00 0 S # Shanks & Pottenger say Toronto ended DST a week early in 1971, # namely on 1971-10-24, but Mark Brader wrote (2003-05-31) that this # is wrong, and that he had confirmed it by checking the 1971-10-30 # Toronto Star, which said that DST was ending 1971-10-31 as usual. Rule Toronto 1957 1973 - Oct lastSun 2:00 0 S # The Bahamas match Toronto since 1970. # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Toronto -5:17:32 - LMT 1895 -5:00 Canada E%sT 1919 -5:00 Toronto E%sT 1942 Feb 9 2:00s -5:00 Canada E%sT 1946 -5:00 Toronto E%sT 1974 -5:00 Canada E%sT # For Atikokan see America/Panama. # Manitoba # From Rob Douglas (2006-04-06): # the old Manitoba Time Act - as amended by Bill 2, assented to # March 27, 1987 ... said ... # "between two o'clock Central Standard Time in the morning of # the first Sunday of April of each year and two o'clock Central # Standard Time in the morning of the last Sunday of October next # following, one hour in advance of Central Standard Time."... # I believe that the English legislation [of the old time act] had # been assented to (March 22, 1967).... # Also, as far as I can tell, there was no order-in-council varying # the time of Daylight Saving Time for 2005 and so the provisions of # the 1987 version would apply - the changeover was at 2:00 Central # Standard Time (i.e. not until 3:00 Central Daylight Time). # From Paul Eggert (2006-04-10): # Shanks & Pottenger say Manitoba switched at 02:00 (not 02:00s) # starting 1966. Since 02:00s is clearly correct for 1967 on, assume # it was also 02:00s in 1966. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Winn 1916 only - Apr 23 0:00 1:00 D Rule Winn 1916 only - Sep 17 0:00 0 S Rule Winn 1918 only - Apr 14 2:00 1:00 D Rule Winn 1918 only - Oct 27 2:00 0 S Rule Winn 1937 only - May 16 2:00 1:00 D Rule Winn 1937 only - Sep 26 2:00 0 S Rule Winn 1942 only - Feb 9 2:00 1:00 W # War Rule Winn 1945 only - Aug 14 23:00u 1:00 P # Peace Rule Winn 1945 only - Sep lastSun 2:00 0 S Rule Winn 1946 only - May 12 2:00 1:00 D Rule Winn 1946 only - Oct 13 2:00 0 S Rule Winn 1947 1949 - Apr lastSun 2:00 1:00 D Rule Winn 1947 1949 - Sep lastSun 2:00 0 S Rule Winn 1950 only - May 1 2:00 1:00 D Rule Winn 1950 only - Sep 30 2:00 0 S Rule Winn 1951 1960 - Apr lastSun 2:00 1:00 D Rule Winn 1951 1958 - Sep lastSun 2:00 0 S Rule Winn 1959 only - Oct lastSun 2:00 0 S Rule Winn 1960 only - Sep lastSun 2:00 0 S Rule Winn 1963 only - Apr lastSun 2:00 1:00 D Rule Winn 1963 only - Sep 22 2:00 0 S Rule Winn 1966 1986 - Apr lastSun 2:00s 1:00 D Rule Winn 1966 2005 - Oct lastSun 2:00s 0 S Rule Winn 1987 2005 - Apr Sun>=1 2:00s 1:00 D # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Winnipeg -6:28:36 - LMT 1887 Jul 16 -6:00 Winn C%sT 2006 -6:00 Canada C%sT # Saskatchewan # From Mark Brader (2003-07-26): # The first actual adoption of DST in Canada was at the municipal # level. As the [Toronto] Star put it (1912-06-07), "While people # elsewhere have long been talking of legislation to save daylight, # the city of Moose Jaw [Saskatchewan] has acted on its own hook." # DST in Moose Jaw began on Saturday, 1912-06-01 (no time mentioned: # presumably late evening, as below), and would run until "the end of # the summer". The discrepancy between municipal time and railroad # time was noted. # From Paul Eggert (2003-07-27): # Willett (1914-03) notes that DST "has been in operation ... in the # City of Moose Jaw, Saskatchewan, for one year." # From Paul Eggert (2019-07-25): # Pearce's book says Regina observed DST in 1914-1917. No dates and times, # unfortunately. It also says that in 1914 Saskatoon observed DST # from 1 June to 6 July, and that DST was also tried out in Davidson, # Melfort, and Prince Albert. # From Paul Eggert (2006-03-22): # Shanks & Pottenger say that since 1970 this region has mostly been as Regina. # Some western towns (e.g. Swift Current) switched from MST/MDT to CST in 1972. # Other western towns (e.g. Lloydminster) are like Edmonton. # Matthews and Vincent (1998) write that Denare Beach and Creighton # are like Winnipeg, in violation of Saskatchewan law. # From W. Jones (1992-11-06): # The. . .below is based on information I got from our law library, the # provincial archives, and the provincial Community Services department. # A precise history would require digging through newspaper archives, and # since you didn't say what you wanted, I didn't bother. # # Saskatchewan is split by a time zone meridian (105W) and over the years # the boundary became pretty ragged as communities near it reevaluated # their affiliations in one direction or the other. In 1965 a provincial # referendum favoured legislating common time practices. # # On 15 April 1966 the Time Act (c. T-14, Revised Statutes of # Saskatchewan 1978) was proclaimed, and established that the eastern # part of Saskatchewan would use CST year round, that districts in # northwest Saskatchewan would by default follow CST but could opt to # follow Mountain Time rules (thus 1 hour difference in the winter and # zero in the summer), and that districts in southwest Saskatchewan would # by default follow MT but could opt to follow CST. # # It took a few years for the dust to settle (I know one story of a town # on one time zone having its school in another, such that a mom had to # serve her family lunch in two shifts), but presently it seems that only # a few towns on the border with Alberta (e.g. Lloydminster) follow MT # rules any more; all other districts appear to have used CST year round # since sometime in the 1960s. # From Chris Walton (2006-06-26): # The Saskatchewan time act which was last updated in 1996 is about 30 pages # long and rather painful to read. # http://www.qp.gov.sk.ca/documents/English/Statutes/Statutes/T14.pdf # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Regina 1918 only - Apr 14 2:00 1:00 D Rule Regina 1918 only - Oct 27 2:00 0 S Rule Regina 1930 1934 - May Sun>=1 0:00 1:00 D Rule Regina 1930 1934 - Oct Sun>=1 0:00 0 S Rule Regina 1937 1941 - Apr Sun>=8 0:00 1:00 D Rule Regina 1937 only - Oct Sun>=8 0:00 0 S Rule Regina 1938 only - Oct Sun>=1 0:00 0 S Rule Regina 1939 1941 - Oct Sun>=8 0:00 0 S Rule Regina 1942 only - Feb 9 2:00 1:00 W # War Rule Regina 1945 only - Aug 14 23:00u 1:00 P # Peace Rule Regina 1945 only - Sep lastSun 2:00 0 S Rule Regina 1946 only - Apr Sun>=8 2:00 1:00 D Rule Regina 1946 only - Oct Sun>=8 2:00 0 S Rule Regina 1947 1957 - Apr lastSun 2:00 1:00 D Rule Regina 1947 1957 - Sep lastSun 2:00 0 S Rule Regina 1959 only - Apr lastSun 2:00 1:00 D Rule Regina 1959 only - Oct lastSun 2:00 0 S # Rule Swift 1957 only - Apr lastSun 2:00 1:00 D Rule Swift 1957 only - Oct lastSun 2:00 0 S Rule Swift 1959 1961 - Apr lastSun 2:00 1:00 D Rule Swift 1959 only - Oct lastSun 2:00 0 S Rule Swift 1960 1961 - Sep lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Regina -6:58:36 - LMT 1905 Sep -7:00 Regina M%sT 1960 Apr lastSun 2:00 -6:00 - CST Zone America/Swift_Current -7:11:20 - LMT 1905 Sep -7:00 Canada M%sT 1946 Apr lastSun 2:00 -7:00 Regina M%sT 1950 -7:00 Swift M%sT 1972 Apr lastSun 2:00 -6:00 - CST # Alberta # From Alois Treindl (2019-07-19): # There was no DST in Alberta in 1967... Calgary Herald, 29 April 1967. # 1969, no DST, from Edmonton Journal 18 April 1969 # # From Paul Eggert (2019-07-25): # Pearce's book says that Alberta's 1948 Daylight Saving Act required # Mountain Standard Time without DST, and that "anyone who broke that law # could be fined up to $25 and costs". There seems to be no record of # anybody paying the fine. The law was not changed until an August 1971 # plebiscite reinstituted DST in 1972. This story is also mentioned in: # Boyer JP. Forcing Choice: The Risky Reward of Referendums. Dundum. 2017. # ISBN 978-1459739123. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D Rule Edm 1918 only - Oct 27 2:00 0 S Rule Edm 1919 only - May 27 2:00 0 S Rule Edm 1920 1923 - Apr lastSun 2:00 1:00 D Rule Edm 1920 only - Oct lastSun 2:00 0 S Rule Edm 1921 1923 - Sep lastSun 2:00 0 S Rule Edm 1942 only - Feb 9 2:00 1:00 W # War Rule Edm 1945 only - Aug 14 23:00u 1:00 P # Peace Rule Edm 1945 only - Sep lastSun 2:00 0 S Rule Edm 1947 only - Apr lastSun 2:00 1:00 D Rule Edm 1947 only - Sep lastSun 2:00 0 S Rule Edm 1972 1986 - Apr lastSun 2:00 1:00 D Rule Edm 1972 2006 - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Edmonton -7:33:52 - LMT 1906 Sep -7:00 Edm M%sT 1987 -7:00 Canada M%sT # British Columbia # From Paul Eggert (2006-03-22): # Shanks & Pottenger write that since 1970 most of this region has # been like Vancouver. # Dawson Creek uses MST. Much of east BC is like Edmonton. # From Matt Johnson (2015-09-21): # Fort Nelson, BC, Canada will cancel DST this year. So while previously they # were aligned with America/Vancouver, they're now aligned with # America/Dawson_Creek. # http://www.northernrockies.ca/EN/meta/news/archives/2015/northern-rockies-time-change.html # # From Tim Parenti (2015-09-23): # This requires a new zone for the Northern Rockies Regional Municipality, # America/Fort_Nelson. The resolution of 2014-12-08 was reached following a # 2014-11-15 poll with nearly 75% support. Effectively, the municipality has # been on MST (-0700) like Dawson Creek since it advanced its clocks on # 2015-03-08. # # From Paul Eggert (2019-07-25): # Shanks says Fort Nelson did not observe DST in 1946, unlike Vancouver. # Alois Treindl confirmed this on 07-22, citing the 1946-04-27 Vancouver Daily # Province. He also cited the 1946-09-28 Victoria Daily Times, which said # that Vancouver, Victoria, etc. "change at midnight Saturday"; for now, # guess they meant 02:00 Sunday since 02:00 was common practice in Vancouver. # # Early Vancouver, Volume Four, by Major J.S. Matthews, V.D., 2011 edition # says that a 1922 plebiscite adopted DST, but a 1923 plebiscite rejected it. # http://former.vancouver.ca/ctyclerk/archives/digitized/EarlyVan/SearchEarlyVan/Vol4pdf/MatthewsEarlyVancouverVol4_DaylightSavings.pdf # A catalog entry for a newspaper clipping seems to indicate that Vancouver # observed DST in 1941 from 07-07 through 09-27; see # https://searcharchives.vancouver.ca/daylight-saving-1918-starts-again-july-7-1941-start-d-s-sept-27-end-of-d-s-1941 # We have no further details, so omit them for now. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Vanc 1918 only - Apr 14 2:00 1:00 D Rule Vanc 1918 only - Oct 27 2:00 0 S Rule Vanc 1942 only - Feb 9 2:00 1:00 W # War Rule Vanc 1945 only - Aug 14 23:00u 1:00 P # Peace Rule Vanc 1945 only - Sep 30 2:00 0 S Rule Vanc 1946 1986 - Apr lastSun 2:00 1:00 D Rule Vanc 1946 only - Sep 29 2:00 0 S Rule Vanc 1947 1961 - Sep lastSun 2:00 0 S Rule Vanc 1962 2006 - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Vancouver -8:12:28 - LMT 1884 -8:00 Vanc P%sT 1987 -8:00 Canada P%sT Zone America/Dawson_Creek -8:00:56 - LMT 1884 -8:00 Canada P%sT 1947 -8:00 Vanc P%sT 1972 Aug 30 2:00 -7:00 - MST Zone America/Fort_Nelson -8:10:47 - LMT 1884 -8:00 Vanc P%sT 1946 -8:00 - PST 1947 -8:00 Vanc P%sT 1987 -8:00 Canada P%sT 2015 Mar 8 2:00 -7:00 - MST # For Creston see America/Phoenix. # Northwest Territories, Nunavut, Yukon # From Chris Walton (2022-11-06): # Whitehorse Star - Thursday April 22, 1965 - page 1 # title: DST Starts Monday ... # https://www.newspapers.com/image/578587481/ # The title of this first article is wrong and/or misleading. # Also, the start time shown in the article is vague; it simply says "after # midnight" when it probably should have stated 2:00a.m.... # # Whitehorse Star - Monday October 25, 1965 - page 15 ... # https://www.newspapers.com/image/578589147/ # The 1965 Yukon Council minutes can be found here: # http://assets.yukonarchives.ca/PER_YG_06_1965_C20_S02_v1.pdf # ... I do not currently believe that NWT touched any of its clocks in 1965.... # # Whitehorse Star - Thursday Feb 24,1966 - page 2 # title: It's Time for YDT ... # https://www.newspapers.com/image/578575979/ ... # America/Whitehorse as a permanent change from UTC-9(YST) to # UTC-8(PST) at 00:00 on Sunday February 27, 1966.... # # Whitehorse Star - Friday April 28,1972 - page 6 # title: Daylight Saving Time for N.W.T.... # https://www.newspapers.com/image/578701610/ ... # Nunavut and NWT zones ... DST starting in 1972.... Start and End ... # should be the same as the rest of Canada # # # From Paul Eggert (2022-11-06): # For now, assume Yukon's 1965-04-22 spring forward was 00:00 -> 02:00, as this # seems likely than 02:00 -> 04:00 and matches "after midnight". # From Paul Eggert (2006-03-22): # Dawson switched to PST in 1973. Inuvik switched to MST in 1979. # Mathew Englander (1996-10-07) gives the following refs: # * 1967. Paragraph 28(34)(g) of the Interpretation Act, S.C. 1967-68, # c. 7 defines Yukon standard time as UTC-9.... # see Interpretation Act, R.S.C. 1985, c. I-21, s. 35(1). # [https://www.canlii.org/en/ca/laws/stat/rsc-1985-c-i-21/latest/rsc-1985-c-i-21.html] # * C.O. 1973/214 switched Yukon to PST on 1973-10-28 00:00. # * O.I.C. 1980/02 established DST. # * O.I.C. 1987/056 changed DST to Apr firstSun 2:00 to Oct lastSun 2:00. # From Brian Inglis (2015-04-14): # # I tried to trace the history of Yukon time and found the following # regulations, giving the reference title and URL if found, regulation name, # and relevant quote if available. Each regulation specifically revokes its # predecessor. The final reference is to the current Interpretation Act # authorizing and resulting from these regulatory changes. # # Only recent regulations were retrievable via Yukon government site search or # index, and only some via Canadian legal sources. Other sources used include # articles titled "Standard Time and Time Zones in Canada" from JRASC via ADS # Abstracts, cited by ADO for 1932 ..., and updated versions from 1958 and # 1970 quoted below; each article includes current extracts from provincial # and territorial ST and DST regulations at the end, summaries and details of # standard times and daylight saving time at many locations across Canada, # with time zone maps, tables and calculations for Canadian Sunrise, Sunset, # and LMST; they also cover many countries and global locations, with a chart # and table showing current Universal Time offsets, and may be useful as # another source of information for 1970 and earlier. # # * Standard Time and Time Zones in Canada; Smith, C.C.; JRASC, Vol. 26, # pp.49-77; February 1932; SAO/NASA Astrophysics Data System (ADS) # http://adsabs.harvard.edu/abs/1932JRASC..26...49S from p.75: # Yukon Interpretation Ordinance # Yukon standard time is the local mean time at the one hundred and # thirty-fifth meridian. # # * Standard Time and Time Zones in Canada; Smith, C.C.; Thomson, Malcolm M.; # JRASC, Vol. 52, pp.193-223; October 1958; SAO/NASA Astrophysics Data System # (ADS) http://adsabs.harvard.edu/abs/1958JRASC..52..193S from pp.220-1: # Yukon Interpretation Ordinance, 1955, Chap. 16. # # (1) Subject to this section, standard time shall be reckoned as nine # hours behind Greenwich Time and called Yukon Standard Time. # # (2) Notwithstanding subsection (1), the Commissioner may make regulations # varying the manner of reckoning standard time. # # * Yukon Territory Commissioner's Order 1966-20 Interpretation Ordinance # [no online source found] # # * Standard Time and Time Zones in Canada; Thomson, Malcolm M.; JRASC, # Vol. 64, pp.129-162; June 1970; SAO/NASA Astrophysics Data System (ADS) # http://adsabs.harvard.edu/abs/1970JRASC..64..129T from p.156: Yukon # Territory Commissioner's Order 1967-59 Interpretation Ordinance ... # # 1. Commissioner's Order 1966-20 dated at Whitehorse in the Yukon # Territory on 27th January, 1966, is hereby revoked. # # 2. Yukon (East) Standard Time as defined by section 36 of the # Interpretation Ordinance from and after mid-night on the 28th day of May, # 1967 shall be reckoned in the same manner as Pacific Standard Time, that # is to say, eight hours behind Greenwich Time in the area of the Yukon # Territory lying east of the 138th degree longitude west. # # 3. In the remainder of the Territory, lying west of the 138th degree # longitude west, Yukon (West) Standard Time shall be reckoned as nine # hours behind Greenwich Time. # # * Yukon Standard Time defined as Pacific Standard Time, YCO 1973/214 # https://www.canlii.org/en/yk/laws/regu/yco-1973-214/latest/yco-1973-214.html # C.O. 1973/214 INTERPRETATION ACT ... # # 1. Effective October 28, 1973 Commissioner's Order 1967/59 is hereby # revoked. # # 2. Yukon Standard Time as defined by section 36 of the Interpretation # Act from and after midnight on the twenty-eighth day of October, 1973 # shall be reckoned in the same manner as Pacific Standard Time, that is # to say eight hours behind Greenwich Time. # # * O.I.C. 1980/02 INTERPRETATION ACT # https://mm.icann.org/pipermail/tz/attachments/20201125/d5adc93b/CAYTOIC1980-02DST1980-01-04-0001.pdf # # * Yukon Daylight Saving Time, YOIC 1987/56 # https://www.canlii.org/en/yk/laws/regu/yoic-1987-56/latest/yoic-1987-56.html # O.I.C. 1987/056 INTERPRETATION ACT ... # # In every year between # (a) two o'clock in the morning in the first Sunday in April, and # (b) two o'clock in the morning in the last Sunday in October, # Standard Time shall be reckoned as seven hours behind Greenwich Time and # called Yukon Daylight Saving Time. # ... # Dated ... 9th day of March, A.D., 1987. # # * Yukon Daylight Saving Time 2006, YOIC 2006/127 # https://www.canlii.org/en/yk/laws/regu/yoic-2006-127/latest/yoic-2006-127.html # O.I.C. 2006/127 INTERPRETATION ACT ... # # 1. In Yukon each year the time for general purposes shall be 7 hours # behind Greenwich mean time during the period commencing at two o'clock # in the forenoon on the second Sunday of March and ending at two o'clock # in the forenoon on the first Sunday of November and shall be called # Yukon Daylight Saving Time. # # 2. Order-in-Council 1987/56 is revoked. # # 3. This order comes into force January 1, 2007. # # * Interpretation Act, RSY 2002, c 125 # https://www.canlii.org/en/yk/laws/stat/rsy-2002-c-125/latest/rsy-2002-c-125.html # From Chris Walton (2022-11-06): # The 5th edition of the Atlas of Canada contains a time zone map that # shows both legislated and observed time zone boundaries. # All communities on Baffin Island are shown to be observing Eastern time. # The date on the map is 1984. # https://ftp.maps.canada.ca/pub/nrcan_rncan/raster/atlas_5_ed/eng/other/referencemaps/mcr4056.pdf # From Rives McDow (1999-09-04): # Nunavut ... moved ... to incorporate the whole territory into one time zone. # Nunavut moves to single time zone Oct. 31 # http://www.nunatsiaq.com/nunavut/nvt90903_13.html # From Paul Eggert (1999-09-20): # Basic Facts: The New Territory # http://www.nunavut.com/basicfacts/english/basicfacts_1territory.html # (1999) reports that ... Coral Harbour does not observe DST. # From Paul Eggert (2000-10-02): # Matthews and Vincent (1998) say the following, but we lack histories # for these potential new Zones. # # The Canadian Forces station at Alert uses Eastern Time while the # handful of residents at the Eureka weather station [in the Central # zone] skip daylight savings. Baffin Island, which is crossed by the # Central, Eastern and Atlantic Time zones only uses Eastern Time. # Gjoa Haven, Taloyoak and Pelly Bay all use Mountain instead of # Central Time and Southampton Island [in the Central zone] is not # required to use daylight savings. # From # Nunavut now has two time zones (2000-11-10): # The Nunavut government would allow its employees in Kugluktuk and # Cambridge Bay to operate on central time year-round, putting them # one hour behind the rest of Nunavut for six months during the winter. # At the end of October the two communities had rebelled against # Nunavut's unified time zone, refusing to shift to eastern time with # the rest of the territory for the winter. Cambridge Bay remained on # central time, while Kugluktuk, even farther west, reverted to # mountain time, which they had used before the advent of Nunavut's # unified time zone in 1999. # # From Rives McDow (2001-01-20), quoting the Nunavut government: # The preceding decision came into effect at midnight, Saturday Nov 4, 2000. # From Paul Eggert (2000-12-04): # Let's just keep track of the official times for now. # From Rives McDow (2001-03-07): # The premier of Nunavut has issued a ministerial statement advising # that effective 2001-04-01, the territory of Nunavut will revert # back to three time zones (mountain, central, and eastern). Of the # cities in Nunavut, Coral Harbor is the only one that I know of that # has said it will not observe dst, staying on EST year round. I'm # checking for more info, and will get back to you if I come up with # more. # [Also see (2001-03-09).] # From Gwillim Law (2005-05-21): # According to ... # http://www.canadiangeographic.ca/Magazine/SO98/geomap.asp # (from a 1998 Canadian Geographic article), the de facto and de jure time # for Southampton Island (at the north end of Hudson Bay) is UTC-5 all year # round. Using Google, it's easy to find other websites that confirm this. # I wasn't able to find how far back this time regimen goes, but since it # predates the creation of Nunavut, it probably goes back many years.... # The Inuktitut name of Coral Harbour is Sallit, but it's rarely used. # # From Paul Eggert (2014-10-17): # For lack of better information, assume that Southampton Island observed # daylight saving only during wartime. Gwillim Law's email also # mentioned maps now maintained by National Research Council Canada; # see above for an up-to-date link. # From Chris Walton (2007-03-01): # ... the community of Resolute (located on Cornwallis Island in # Nunavut) moved from Central Time to Eastern Time last November. # Basically the community did not change its clocks at the end of # daylight saving.... # http://www.nnsl.com/frames/newspapers/2006-11/nov13_06none.html # From Chris Walton (2011-03-21): # Back in 2007 I initiated the creation of a new "zone file" for Resolute # Bay. Resolute Bay is a small community located about 900km north of # the Arctic Circle. The zone file was required because Resolute Bay had # decided to use UTC-5 instead of UTC-6 for the winter of 2006-2007. # # According to new information which I received last week, Resolute Bay # went back to using UTC-6 in the winter of 2007-2008... # # On March 11/2007 most of Canada went onto daylight saving. On March # 14/2007 I phoned the Resolute Bay hamlet office to do a "time check." I # talked to somebody that was both knowledgeable and helpful. I was able # to confirm that Resolute Bay was still operating on UTC-5. It was # explained to me that Resolute Bay had been on the Eastern Time zone # (EST) in the winter, and was now back on the Central Time zone (CDT). # i.e. the time zone had changed twice in the last year but the clocks # had not moved. The residents had to know which time zone they were in # so they could follow the correct TV schedule... # # On Nov 02/2008 most of Canada went onto standard time. On Nov 03/2008 I # phoned the Resolute Bay hamlet office...[D]ue to the challenging nature # of the phone call, I decided to seek out an alternate source of # information. I found an e-mail address for somebody by the name of # Stephanie Adams whose job was listed as "Inns North Support Officer for # Arctic Co-operatives." I was under the impression that Stephanie lived # and worked in Resolute Bay... # # On March 14/2011 I phoned the hamlet office again. I was told that # Resolute Bay had been using Central Standard Time over the winter of # 2010-2011 and that the clocks had therefore been moved one hour ahead # on March 13/2011. The person I talked to was aware that Resolute Bay # had previously experimented with Eastern Standard Time but he could not # tell me when the practice had stopped. # # On March 17/2011 I searched the Web to find an e-mail address of # somebody that might be able to tell me exactly when Resolute Bay went # off Eastern Standard Time. I stumbled on the name "Aziz Kheraj." Aziz # used to be the mayor of Resolute Bay and he apparently owns half the # businesses including "South Camp Inn." This website has some info on # Aziz: # http://www.uphere.ca/node/493 # # I sent Aziz an e-mail asking when Resolute Bay had stopped using # Eastern Standard Time. # # Aziz responded quickly with this: "hi, The time was not changed for the # 1 year only, the following year, the community went back to the old way # of "spring ahead-fall behind" currently we are zulu plus 5 hrs and in # the winter Zulu plus 6 hrs" # # This of course conflicted with everything I had ascertained in November 2008. # # I sent Aziz a copy of my 2008 e-mail exchange with Stephanie. Aziz # responded with this: "Hi, Stephanie lives in Winnipeg. I live here, You # may want to check with the weather office in Resolute Bay or do a # search on the weather through Env. Canada. web site" # # If I had realized the Stephanie did not live in Resolute Bay I would # never have contacted her. I now believe that all the information I # obtained in November 2008 should be ignored... # I apologize for reporting incorrect information in 2008. # From Tim Parenti (2020-03-05): # The government of Yukon announced [yesterday] the cessation of seasonal time # changes. "After clocks are pushed ahead one hour on March 8, the territory # will remain on [UTC-07]. ... [The government] found 93 per cent of # respondents wanted to end seasonal time changes and, of that group, 70 per # cent wanted 'permanent Pacific Daylight Saving Time.'" # https://www.cbc.ca/news/canada/north/yukon-end-daylight-saving-time-1.5486358 # # Although the government press release prefers PDT, we prefer MST for # consistency with nearby Dawson Creek, Creston, and Fort Nelson. # https://yukon.ca/en/news/yukon-end-seasonal-time-change # From Andrew G. Smith (2020-09-24): # Yukon has completed its regulatory change to be on UTC -7 year-round.... # http://www.gov.yk.ca/legislation/regs/oic2020_125.pdf # What we have done is re-defined Yukon Standard Time, as we are # authorized to do under section 33 of our Interpretation Act: # http://www.gov.yk.ca/legislation/acts/interpretation_c.pdf # # From Paul Eggert (2020-09-24): # tzdb uses the obsolete YST abbreviation for standard time in Yukon through # about 1970, and uses PST for standard time in Yukon since then. Consistent # with that, use MST for -07, the new standard time in Yukon effective Nov. 1. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule NT_YK 1918 only - Apr 14 2:00 1:00 D Rule NT_YK 1918 only - Oct 27 2:00 0 S Rule NT_YK 1919 only - May 25 2:00 1:00 D Rule NT_YK 1919 only - Nov 1 0:00 0 S Rule NT_YK 1942 only - Feb 9 2:00 1:00 W # War Rule NT_YK 1945 only - Aug 14 23:00u 1:00 P # Peace Rule NT_YK 1945 only - Sep 30 2:00 0 S Rule NT_YK 1972 1986 - Apr lastSun 2:00 1:00 D Rule NT_YK 1972 2006 - Oct lastSun 2:00 0 S Rule NT_YK 1987 2006 - Apr Sun>=1 2:00 1:00 D Rule Yukon 1965 only - Apr lastSun 0:00 2:00 DD Rule Yukon 1965 only - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] # formerly Frobisher Bay Zone America/Iqaluit 0 - -00 1942 Aug # Frobisher Bay est. -5:00 NT_YK E%sT 1999 Oct 31 2:00 -6:00 Canada C%sT 2000 Oct 29 2:00 -5:00 Canada E%sT # aka Qausuittuq Zone America/Resolute 0 - -00 1947 Aug 31 # Resolute founded -6:00 NT_YK C%sT 2000 Oct 29 2:00 -5:00 - EST 2001 Apr 1 3:00 -6:00 Canada C%sT 2006 Oct 29 2:00 -5:00 - EST 2007 Mar 11 3:00 -6:00 Canada C%sT # aka Kangiqiniq Zone America/Rankin_Inlet 0 - -00 1957 # Rankin Inlet founded -6:00 NT_YK C%sT 2000 Oct 29 2:00 -5:00 - EST 2001 Apr 1 3:00 -6:00 Canada C%sT # aka Iqaluktuuttiaq Zone America/Cambridge_Bay 0 - -00 1920 # trading post est.? -7:00 NT_YK M%sT 1999 Oct 31 2:00 -6:00 Canada C%sT 2000 Oct 29 2:00 -5:00 - EST 2000 Nov 5 0:00 -6:00 - CST 2001 Apr 1 3:00 -7:00 Canada M%sT Zone America/Inuvik 0 - -00 1953 # Inuvik founded -8:00 NT_YK P%sT 1979 Apr lastSun 2:00 -7:00 NT_YK M%sT 1980 -7:00 Canada M%sT Zone America/Whitehorse -9:00:12 - LMT 1900 Aug 20 -9:00 NT_YK Y%sT 1965 -9:00 Yukon Y%sT 1966 Feb 27 0:00 -8:00 - PST 1980 -8:00 Canada P%sT 2020 Nov 1 -7:00 - MST Zone America/Dawson -9:17:40 - LMT 1900 Aug 20 -9:00 NT_YK Y%sT 1965 -9:00 Yukon Y%sT 1973 Oct 28 0:00 -8:00 - PST 1980 -8:00 Canada P%sT 2020 Nov 1 -7:00 - MST ############################################################################### # Mexico # From Paul Eggert (2014-12-07): # The Investigation and Analysis Service of the # Mexican Library of Congress (MLoC) has published a # history of Mexican local time (in Spanish) # http://www.diputados.gob.mx/bibliot/publica/inveyana/polisoc/horver/index.htm # # Here are the discrepancies between Shanks & Pottenger (S&P) and the MLoC. # (In all cases we go with the MLoC.) # S&P report that Baja was at -8:00 in 1922/1923. # S&P say the 1930 transition in Baja was 1930-11-16. # S&P report no DST during summer 1931. # S&P report a transition at 1932-03-30 23:00, not 1932-04-01. # From Gwillim Law (2001-02-20): # There are some other discrepancies between the Decrees page and the # tz database. I think they can best be explained by supposing that # the researchers who prepared the Decrees page failed to find some of # the relevant documents. # From Alan Perry (1996-02-15): # A guy from our Mexico subsidiary finally found the Presidential Decree # outlining the timezone changes in Mexico. # # ------------- Begin Forwarded Message ------------- # # I finally got my hands on the Official Presidential Decree that sets up the # rules for the DST changes. The rules are: # # 1. The country is divided in 3 timezones: # - Baja California Norte (the Mexico/BajaNorte TZ) # - Baja California Sur, Nayarit, Sinaloa and Sonora (the Mexico/BajaSur TZ) # - The rest of the country (the Mexico/General TZ) # # 2. From the first Sunday in April at 2:00 AM to the last Sunday in October # at 2:00 AM, the times in each zone are as follows: # BajaNorte: GMT+7 # BajaSur: GMT+6 # General: GMT+5 # # 3. The rest of the year, the times are as follows: # BajaNorte: GMT+8 # BajaSur: GMT+7 # General: GMT+6 # # The Decree was published in Mexico's Official Newspaper on January 4th. # # -------------- End Forwarded Message -------------- # From Paul Eggert (1996-06-12): # For an English translation of the decree, see # "Diario Oficial: Time Zone Changeover" (1996-01-04). # http://mexico-travel.com/extra/timezone_eng.html # From Rives McDow (1998-10-08): # The State of Quintana Roo has reverted back to central STD and DST times # (i.e. UTC -0600 and -0500 as of 1998-08-02). # From Rives McDow (2000-01-10): # Effective April 4, 1999 at 2:00 AM local time, Sonora changed to the time # zone 5 hours from the International Date Line, and will not observe daylight # savings time so as to stay on the same time zone as the southern part of # Arizona year round. # From Jesper Nørgaard, translating # (2001-01-17): # In Oaxaca, the 55.000 teachers from the Section 22 of the National # Syndicate of Education Workers, refuse to apply daylight saving each # year, so that the more than 10,000 schools work at normal hour the # whole year. # From Gwillim Law (2001-01-19): # ... says # (translated):... # January 17, 2000 - The Energy Secretary, Ernesto Martens, announced # that Summer Time will be reduced from seven to five months, starting # this year.... # http://www.publico.com.mx/scripts/texto3.asp?action=pagina&pag=21&pos=p&secc=naci&date=01/17/2001 # [translated], says "summer time will ... take effect on the first Sunday # in May, and end on the last Sunday of September. # From Arthur David Olson (2001-01-25): # The 2001-01-24 traditional Washington Post contained the page one # story "Timely Issue Divides Mexicans."... # http://www.washingtonpost.com/wp-dyn/articles/A37383-2001Jan23.html # ... Mexico City Mayor López Obrador "...is threatening to keep # Mexico City and its 20 million residents on a different time than # the rest of the country..." In particular, López Obrador would abolish # observation of Daylight Saving Time. # Official statute published by the Energy Department # http://www.conae.gob.mx/ahorro/decretohorver2001.html#decre # (2001-02-01) shows Baja and Chihauhua as still using US DST rules, # and Sonora with no DST. This was reported by Jesper Nørgaard (2001-02-03). # From Paul Eggert (2001-03-03): # # https://www.latimes.com/archives/la-xpm-2001-mar-03-mn-32561-story.html # James F. Smith writes in today's LA Times # * Sonora will continue to observe standard time. # * Last week Mexico City's mayor Andrés Manuel López Obrador decreed that # the Federal District will not adopt DST. # * 4 of 16 district leaders announced they'll ignore the decree. # * The decree does not affect federal-controlled facilities including # the airport, banks, hospitals, and schools. # # For now we'll assume that the Federal District will bow to federal rules. # From Jesper Nørgaard (2001-04-01): # I found some references to the Mexican application of daylight # saving, which modifies what I had already sent you, stating earlier # that a number of northern Mexican states would go on daylight # saving. The modification reverts this to only cover Baja California # (Norte), while all other states (except Sonora, who has no daylight # saving all year) will follow the original decree of president # Vicente Fox, starting daylight saving May 6, 2001 and ending # September 30, 2001. # References: "Diario de Monterrey" # Palabra (2001-03-31) # From Reuters (2001-09-04): # Mexico's Supreme Court on Tuesday declared that daylight savings was # unconstitutional in Mexico City, creating the possibility the # capital will be in a different time zone from the rest of the nation # next year.... The Supreme Court's ruling takes effect at 2:00 # a.m. (0800 GMT) on Sept. 30, when Mexico is scheduled to revert to # standard time. "This is so residents of the Federal District are not # subject to unexpected time changes," a statement from the court said. # From Jesper Nørgaard Welen (2002-03-12): # ... consulting my local grocery store(!) and my coworkers, they all insisted # that a new decision had been made to reinstate US style DST in Mexico.... # http://www.conae.gob.mx/ahorro/horaver2001_m1_2002.html (2002-02-20) # confirms this. Sonora as usual is the only state where DST is not applied. # From Steffen Thorsen (2009-12-28): # # Steffen Thorsen wrote: # > Mexico's House of Representatives has approved a proposal for northern # > Mexico's border cities to share the same daylight saving schedule as # > the United States. # Now this has passed both the Congress and the Senate, so starting from # 2010, some border regions will be the same: # http://www.signonsandiego.com/news/2009/dec/28/clocks-will-match-both-sides-border/ # http://www.elmananarey.com/diario/noticia/nacional/noticias/empatan_horario_de_frontera_con_eu/621939 # (Spanish) # # Could not find the new law text, but the proposed law text changes are here: # http://gaceta.diputados.gob.mx/Gaceta/61/2009/dic/20091210-V.pdf # (Gaceta Parlamentaria) # # There is also a list of the votes here: # http://gaceta.diputados.gob.mx/Gaceta/61/2009/dic/V2-101209.html # # Our page: # https://www.timeanddate.com/news/time/north-mexico-dst-change.html # From Arthur David Olson (2010-01-20): # The page # http://dof.gob.mx/nota_detalle.php?codigo=5127480&fecha=06/01/2010 # includes this text: # En los municipios fronterizos de Tijuana y Mexicali en Baja California; # Juárez y Ojinaga en Chihuahua; Acuña y Piedras Negras en Coahuila; # Anáhuac en Nuevo León; y Nuevo Laredo, Reynosa y Matamoros en # Tamaulipas, la aplicación de este horario estacional surtirá efecto # desde las dos horas del segundo domingo de marzo y concluirá a las dos # horas del primer domingo de noviembre. # En los municipios fronterizos que se encuentren ubicados en la franja # fronteriza norte en el territorio comprendido entre la línea # internacional y la línea paralela ubicada a una distancia de veinte # kilómetros, así como la Ciudad de Ensenada, Baja California, hacia el # interior del país, la aplicación de este horario estacional surtirá # efecto desde las dos horas del segundo domingo de marzo y concluirá a # las dos horas del primer domingo de noviembre. # From Steffen Thorsen (2014-12-08), translated by Gwillim Law: # The Mexican state of Quintana Roo will likely change to EST in 2015. # # http://www.unioncancun.mx/articulo/2014/12/04/medio-ambiente/congreso-aprueba-una-hora-mas-de-sol-en-qroo # "With this change, the time conflict that has existed between the municipios # of Quintana Roo and the municipio of Felipe Carrillo Puerto may come to an # end. The latter declared itself in rebellion 15 years ago when a time change # was initiated in Mexico, and since then it has refused to change its time # zone along with the rest of the country." # # From Steffen Thorsen (2015-01-14), translated by Gwillim Law: # http://sipse.com/novedades/confirman-aplicacion-de-nueva-zona-horaria-para-quintana-roo-132331.html # "...the new time zone will come into effect at two o'clock on the first Sunday # of February, when we will have to advance the clock one hour from its current # time..." # Also, the new zone will not use DST. # # From Carlos Raúl Perasso (2015-02-02): # The decree that modifies the Mexican Hour System Law has finally # been published at the Diario Oficial de la Federación # http://www.dof.gob.mx/nota_detalle.php?codigo=5380123&fecha=31/01/2015 # It establishes 5 zones for Mexico: # 1- Zona Centro (Central Zone): Corresponds to longitude 90 W, # includes most of Mexico, excluding what's mentioned below. # 2- Zona Pacífico (Pacific Zone): Longitude 105 W, includes the # states of Baja California Sur; Chihuahua; Nayarit (excluding Bahía # de Banderas which lies in Central Zone); Sinaloa and Sonora. # 3- Zona Noroeste (Northwest Zone): Longitude 120 W, includes the # state of Baja California. # 4- Zona Sureste (Southeast Zone): Longitude 75 W, includes the state # of Quintana Roo. # 5- The islands, reefs and keys shall take their timezone from the # longitude they are located at. # From Paul Eggert (2022-10-28): # The new Mexican law was published today: # https://www.dof.gob.mx/nota_detalle.php?codigo=5670045&fecha=28/10/2022 # This abolishes DST except where US DST rules are observed, # and in addition changes all of Chihuahua to -06 with no DST. # From Heitor David Pinto (2022-11-28): # Now the northern [municipios] want to have the same time zone as the # respective neighboring cities in the US, for example Juárez in UTC-7 with # DST, matching El Paso, and Ojinaga in UTC-6 with DST, matching Presidio.... # the president authorized the publication of the decree for November 29, # so the time change would occur on November 30 at 0:00. # http://puentelibre.mx/noticia/ciudad_juarez_cambio_horario_noviembre_2022/ # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Mexico 1931 only - May 1 23:00 1:00 D Rule Mexico 1931 only - Oct 1 0:00 0 S Rule Mexico 1939 only - Feb 5 0:00 1:00 D Rule Mexico 1939 only - Jun 25 0:00 0 S Rule Mexico 1940 only - Dec 9 0:00 1:00 D Rule Mexico 1941 only - Apr 1 0:00 0 S Rule Mexico 1943 only - Dec 16 0:00 1:00 W # War Rule Mexico 1944 only - May 1 0:00 0 S Rule Mexico 1950 only - Feb 12 0:00 1:00 D Rule Mexico 1950 only - Jul 30 0:00 0 S Rule Mexico 1996 2000 - Apr Sun>=1 2:00 1:00 D Rule Mexico 1996 2000 - Oct lastSun 2:00 0 S Rule Mexico 2001 only - May Sun>=1 2:00 1:00 D Rule Mexico 2001 only - Sep lastSun 2:00 0 S Rule Mexico 2002 2022 - Apr Sun>=1 2:00 1:00 D Rule Mexico 2002 2022 - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] # Quintana Roo; represented by Cancún Zone America/Cancun -5:47:04 - LMT 1922 Jan 1 6:00u -6:00 - CST 1981 Dec 23 -5:00 Mexico E%sT 1998 Aug 2 2:00 -6:00 Mexico C%sT 2015 Feb 1 2:00 -5:00 - EST # Campeche, Yucatán; represented by Mérida Zone America/Merida -5:58:28 - LMT 1922 Jan 1 6:00u -6:00 - CST 1981 Dec 23 -5:00 - EST 1982 Dec 2 -6:00 Mexico C%sT # Coahuila, Nuevo León, Tamaulipas (near US border) # This includes the following municipios: # in Coahuila: Acuña, Allende, Guerrero, Hidalgo, Jiménez, Morelos, Nava, # Ocampo, Piedras Negras, Villa Unión, Zaragoza # in Nuevo León: Anáhuac # in Tamaulipas: Nuevo Laredo, Guerrero, Mier, Miguel Alemán, Camargo, # Gustavo Díaz Ordaz, Reynosa, Río Bravo, Valle Hermoso, Matamoros. # https://www.dof.gob.mx/nota_detalle.php?codigo=5670045&fecha=28/10/2022 Zone America/Matamoros -6:30:00 - LMT 1922 Jan 1 6:00u -6:00 - CST 1988 -6:00 US C%sT 1989 -6:00 Mexico C%sT 2010 -6:00 US C%sT # Durango; Coahuila, Nuevo León, Tamaulipas (away from US border) Zone America/Monterrey -6:41:16 - LMT 1922 Jan 1 6:00u -6:00 - CST 1988 -6:00 US C%sT 1989 -6:00 Mexico C%sT # Central Mexico Zone America/Mexico_City -6:36:36 - LMT 1922 Jan 1 7:00u -7:00 - MST 1927 Jun 10 23:00 -6:00 - CST 1930 Nov 15 -7:00 Mexico M%sT 1932 Apr 1 -6:00 Mexico C%sT 2001 Sep 30 2:00 -6:00 - CST 2002 Feb 20 -6:00 Mexico C%sT # Chihuahua (near US border - western side) # This includes the municipios of Janos, Ascensión, Juárez, Guadalupe, and # Práxedis G Guerrero. # http://gaceta.diputados.gob.mx/PDF/65/2a022/nov/20221124-VII.pdf Zone America/Ciudad_Juarez -7:05:56 - LMT 1922 Jan 1 7:00u -7:00 - MST 1927 Jun 10 23:00 -6:00 - CST 1930 Nov 15 -7:00 Mexico M%sT 1932 Apr 1 -6:00 - CST 1996 -6:00 Mexico C%sT 1998 -6:00 - CST 1998 Apr Sun>=1 3:00 -7:00 Mexico M%sT 2010 -7:00 US M%sT 2022 Oct 30 2:00 -6:00 - CST 2022 Nov 30 0:00 -7:00 US M%sT # Chihuahua (near US border - eastern side) # This includes the municipios of Coyame del Sotol, Ojinaga, and Manuel # Benavides. # http://gaceta.diputados.gob.mx/PDF/65/2a022/nov/20221124-VII.pdf Zone America/Ojinaga -6:57:40 - LMT 1922 Jan 1 7:00u -7:00 - MST 1927 Jun 10 23:00 -6:00 - CST 1930 Nov 15 -7:00 Mexico M%sT 1932 Apr 1 -6:00 - CST 1996 -6:00 Mexico C%sT 1998 -6:00 - CST 1998 Apr Sun>=1 3:00 -7:00 Mexico M%sT 2010 -7:00 US M%sT 2022 Oct 30 2:00 -6:00 - CST 2022 Nov 30 0:00 -6:00 US C%sT # Chihuahua (away from US border) Zone America/Chihuahua -7:04:20 - LMT 1922 Jan 1 7:00u -7:00 - MST 1927 Jun 10 23:00 -6:00 - CST 1930 Nov 15 -7:00 Mexico M%sT 1932 Apr 1 -6:00 - CST 1996 -6:00 Mexico C%sT 1998 -6:00 - CST 1998 Apr Sun>=1 3:00 -7:00 Mexico M%sT 2022 Oct 30 2:00 -6:00 - CST # Sonora Zone America/Hermosillo -7:23:52 - LMT 1922 Jan 1 7:00u -7:00 - MST 1927 Jun 10 23:00 -6:00 - CST 1930 Nov 15 -7:00 Mexico M%sT 1932 Apr 1 -6:00 - CST 1942 Apr 24 -7:00 - MST 1949 Jan 14 -8:00 - PST 1970 -7:00 Mexico M%sT 1999 -7:00 - MST # Baja California Sur, Nayarit (except Bahía de Banderas), Sinaloa Zone America/Mazatlan -7:05:40 - LMT 1922 Jan 1 7:00u -7:00 - MST 1927 Jun 10 23:00 -6:00 - CST 1930 Nov 15 -7:00 Mexico M%sT 1932 Apr 1 -6:00 - CST 1942 Apr 24 -7:00 - MST 1949 Jan 14 -8:00 - PST 1970 -7:00 Mexico M%sT # Bahía de Banderas # From Alexander Krivenyshev (2010-04-21): # According to news, Bahía de Banderas (Mexican state of Nayarit) # changed time zone UTC-7 to new time zone UTC-6 on April 4, 2010 (to # share the same time zone as nearby city Puerto Vallarta, Jalisco). # # (Spanish) # Bahía de Banderas homologa su horario al del centro del # país, a partir de este domingo # http://www.nayarit.gob.mx/notes.asp?id=20748 # # Bahía de Banderas homologa su horario con el del Centro del # País # http://www.bahiadebanderas.gob.mx/principal/index.php?option=com_content&view=article&id=261:bahia-de-banderas-homologa-su-horario-con-el-del-centro-del-pais&catid=42:comunicacion-social&Itemid=50 # # (English) # Puerto Vallarta and Bahía de Banderas: One Time Zone # http://virtualvallarta.com/puertovallarta/puertovallarta/localnews/2009-12-03-Puerto-Vallarta-and-Bahia-de-Banderas-One-Time-Zone.shtml # http://www.worldtimezone.com/dst_news/dst_news_mexico08.html # # "Mexico's Senate approved the amendments to the Mexican Schedule System that # will allow Bahía de Banderas and Puerto Vallarta to share the same time # zone ..." # Baja California Sur, Nayarit, Sinaloa # From Arthur David Olson (2010-05-01): # Use "Bahia_Banderas" to keep the name to fourteen characters. Zone America/Bahia_Banderas -7:01:00 - LMT 1922 Jan 1 7:00u -7:00 - MST 1927 Jun 10 23:00 -6:00 - CST 1930 Nov 15 -7:00 Mexico M%sT 1932 Apr 1 -6:00 - CST 1942 Apr 24 -7:00 - MST 1949 Jan 14 -8:00 - PST 1970 -7:00 Mexico M%sT 2010 Apr 4 2:00 -6:00 Mexico C%sT # Baja California Zone America/Tijuana -7:48:04 - LMT 1922 Jan 1 7:00u -7:00 - MST 1924 -8:00 - PST 1927 Jun 10 23:00 -7:00 - MST 1930 Nov 15 -8:00 - PST 1931 Apr 1 -8:00 1:00 PDT 1931 Sep 30 -8:00 - PST 1942 Apr 24 -8:00 1:00 PWT 1945 Aug 14 23:00u -8:00 1:00 PPT 1945 Nov 12 # Peace -8:00 - PST 1948 Apr 5 -8:00 1:00 PDT 1949 Jan 14 -8:00 - PST 1954 -8:00 CA P%sT 1961 -8:00 - PST 1976 -8:00 US P%sT 1996 -8:00 Mexico P%sT 2001 -8:00 US P%sT 2002 Feb 20 -8:00 Mexico P%sT 2010 -8:00 US P%sT # From Paul Eggert (2006-03-22): # Formerly there was an America/Ensenada zone, which differed from # America/Tijuana only in that it did not observe DST from 1976 # through 1995. This was as per Shanks (1999). But Shanks & Pottenger say # Ensenada did not observe DST from 1948 through 1975. Guy Harris reports # that the 1987 OAG says "Only Ensenada, Mexicali, San Felipe and # Tijuana observe DST," which agrees with Shanks & Pottenger but implies that # DST-observance was a town-by-town matter back then. This concerns # data after 1970 so most likely there should be at least one Zone # other than America/Tijuana for Baja, but it's not clear yet what its # name or contents should be. # # From Paul Eggert (2015-10-08): # Formerly there was an America/Santa_Isabel zone, but this appears to # have come from a misreading of # http://dof.gob.mx/nota_detalle.php?codigo=5127480&fecha=06/01/2010 # It has been moved to the 'backward' file. # # From Paul Eggert (2022-10-28): # Today's new law states that the entire state of Baja California # follows US DST rules, which agrees with simplifications noted above. # # # Revillagigedo Is # no information ############################################################################### # Barbados # For 1899 Milne gives -3:58:29.2. # From P Chan (2020-12-09 and 2020-12-11): # Standard time of GMT-4 was adopted in 1911. # Definition of Time Act, 1911 (1911-7) [1911-08-28] # 1912, Laws of Barbados (5 v.), OCLC Number: 919801291, Vol. 4, Image No. 522 # 1944, Laws of Barbados (5 v.), OCLC Number: 84548697, Vol. 4, Image No. 122 # http://llmc.com/browse.aspx?type=2&coll=85&div=297 # # DST was observed in 1942-44. # Defence (Daylight Saving) Regulations, 1942, 1942-04-13 # Defence (Daylight Saving) (Repeal) Regulations, 1942, 1942-08-22 # Defence (Daylight Saving) Regulations, 1943, 1943-04-16 # Defence (Daylight Saving) (Repeal) Regulations, 1943, 1943-09-01 # Defence (Daylight Saving) Regulations, 1944, 1944-03-21 # [Defence (Daylight Saving) (Amendment) Regulations 1944, 1944-03-28] # Defence (Daylight Saving) (Repeal) Regulations, 1944, 1944-08-30 # # 1914-, Subsidiary Legis., Annual Vols. OCLC Number: 226290591 # 1942: Image Nos. 527-528, 555-556 # 1943: Image Nos. 178-179, 198 # 1944: Image Nos. 113-115, 129 # http://llmc.com/titledescfull.aspx?type=2&coll=85&div=297&set=98437 # # From Tim Parenti (2021-02-20): # The transitions below are derived from P Chan's sources, except that the 1977 # through 1980 transitions are from Shanks & Pottenger since we have no better # data there. Of particular note, the 1944 DST regulation only advanced the # time to "exactly three and a half hours later than Greenwich mean time", as # opposed to "three hours" in the 1942 and 1943 regulations. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Barb 1942 only - Apr 19 5:00u 1:00 D Rule Barb 1942 only - Aug 31 6:00u 0 S Rule Barb 1943 only - May 2 5:00u 1:00 D Rule Barb 1943 only - Sep 5 6:00u 0 S Rule Barb 1944 only - Apr 10 5:00u 0:30 - Rule Barb 1944 only - Sep 10 6:00u 0 S Rule Barb 1977 only - Jun 12 2:00 1:00 D Rule Barb 1977 1978 - Oct Sun>=1 2:00 0 S Rule Barb 1978 1980 - Apr Sun>=15 2:00 1:00 D Rule Barb 1979 only - Sep 30 2:00 0 S Rule Barb 1980 only - Sep 25 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] #STDOFF -3:58:29.2 Zone America/Barbados -3:58:29 - LMT 1911 Aug 28 # Bridgetown -4:00 Barb A%sT 1944 -4:00 Barb AST/-0330 1945 -4:00 Barb A%sT # Belize # From P Chan (2020-11-03): # Below are some laws related to the time in British Honduras/Belize: # # Definition of Time Ordinance, 1927 (No.4 of 1927) [1927-04-01] # Ordinances of British Honduras Passed in the Year 1927, p 19-20 # https://books.google.com/books?id=LqEpAQAAMAAJ&pg=RA3-PA19 # # Definition of Time (Amendment) Ordinance, 1942 (No. 5 of 1942) [1942-06-27] # Ordinances of British Honduras Passed in the Year 1942, p 31-32 # https://books.google.com/books?id=h6MpAQAAMAAJ&pg=RA6-PA95-IA44 # # Definition of Time Ordinance, 1945 (No. 19 of 1945) [1945-12-15] # Ordinances of British Honduras Passed in the Year 1945, p 49-50 # https://books.google.com/books?id=xaMpAQAAMAAJ&pg=RA2-PP1 # # Definition of Time Ordinance, 1947 (No. 1 of 1947) [1947-03-11] # Ordinances of British Honduras Passed in the Year 1947, p 1-2 # https://books.google.com/books?id=xaMpAQAAMAAJ&pg=RA3-PA1 # # Time (Definition of) Ordinance (Chapter 180) # The Laws of British Honduras in Force on the 15th Day of September, 1958 , Volume IV, p 2580 # https://books.google.com/books?id=v5QpAQAAMAAJ&pg=PA2580 # # Time (Definition of) (Amendment) Ordinance, 1968 (No. 13 of 1968) [1968-08-03] # https://books.google.com/books?id=xij7KEB_58wC&pg=RA1-PA428-IA9 # # Definition of Time Act (Chapter 339) # Law of Belize, Revised Edition 2000 # http://www.belizelaw.org/web/lawadmin/PDF%20files/cap339.pdf # From Paul Eggert (2020-11-03): # The transitions below are derived from P Chan's sources, except that the # 1973 through 1983 transitions are from Shanks & Pottenger since we have # no better data there. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Belize 1918 1941 - Oct Sat>=1 24:00 0:30 -0530 Rule Belize 1919 1942 - Feb Sat>=8 24:00 0 CST Rule Belize 1942 only - Jun 27 24:00 1:00 CWT Rule Belize 1945 only - Aug 14 23:00u 1:00 CPT Rule Belize 1945 only - Dec 15 24:00 0 CST Rule Belize 1947 1967 - Oct Sat>=1 24:00 0:30 -0530 Rule Belize 1948 1968 - Feb Sat>=8 24:00 0 CST Rule Belize 1973 only - Dec 5 0:00 1:00 CDT Rule Belize 1974 only - Feb 9 0:00 0 CST Rule Belize 1982 only - Dec 18 0:00 1:00 CDT Rule Belize 1983 only - Feb 12 0:00 0 CST # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Belize -5:52:48 - LMT 1912 Apr 1 -6:00 Belize %s # Bermuda # From Paul Eggert (2022-07-27): # For 1899 Milne gives -4:19:18.3 as the meridian of the clock tower, # Bermuda dockyard, Ireland I. This agrees with standard offset given in the # Daylight Saving Act, 1917 cited below. # It is not known when this time became standard for Bermuda; guess 1890. # The transition to -04 was specified by: # 1930: The Time Zone Act, 1929 (1929: No. 39) [1929-11-08] # https://books.google.com/books?id=7tdMAQAAIAAJ&pg=RA54-PP1 # From P Chan (2020-11-20): # Most of the information can be found online from the Bermuda National # Library - Digital Collection which includes The Royal Gazette (RG) until 1957 # https://bnl.contentdm.oclc.org/digital/ # I will cite the ID. For example, [10000] means # https://bnl.contentdm.oclc.org/digital/collection/BermudaNP02/id/10000 # # 1917: Apr 5 midnight to Sep 30 midnight # Daylight Saving Act, 1917 (1917 No. 13) [1917-04-02] # Bermuda Acts and Resolves 1917, p 37-38 # https://books.google.com/books?id=M-lCAQAAMAAJ&pg=PA36-IA2 # RG, 1917-04-04, p 6 [42340] gives the spring forward date. # # 1918: Apr 13 midnight to Sep 15 midnight # Daylight Saving Act, 1918 (1918 No. 9) [1918-04-06] # Bermuda Acts and Resolves 1917, p 13 # https://books.google.com/books?id=K-lCAQAAMAAJ&pg=RA1-PA7 # # Note that local mean time was still used before 1930. # # During WWII, DST was introduced by Defence Regulations # 1942: Jan 11 02:00 to Oct 18 02:00 [113646], [115726] # 1943: Mar 21 02:00 to Oct 31 02:00 [116704], [118193] # 1944: Mar 12 02:00 to Nov 5 02:00 [119225], [121593] # 1945: Mar 11 02:00 to Nov 4 02:00 [122369], [124461] # RG, 1942-01-08, p 2, 1942-10-12, p 2 , 1943-03-06, p 2, 1943-09-03, p 1, # 1944-02-29, p 6, 1944-09-20, p 2, 1945-02-13, p 2, 1945-11-03, p 1 # # In 1946, the House of Assembly rejected DST twice. [128686], [128076] # RG, 1946-03-16 p 1,1946-04-13 p 1 # # 1947: third Sunday in May 02:00 to second Sunday in September 02:00 # DST in 1947 was defined in the Daylight Saving Act, 1947 (1947: No. 12) # which expired at the end of the year. [125784] ,[132405], [144454], [138226] # RG, 1947-02-27, p 1, 1947-05-15, p 1, 1947-09-13, p 1, 1947-12-30, p 1 # # 1948-1952: fourth Sunday in May 02:00 to first Sunday in September 02:00 # DST in 1948 was defined in the Daylight Saving Act, 1948 (1948 : No. 12) # which was set to expired at the end of the year but it was extended until # the end of 1952 and was not further extended. # [129802], [139403], [146008], [135240], [144330], [139049], [143309], # [148271], [149773], [153589], [153802], [155924] # RG, 1948-04-13, p 1, 1948-05-22, p 1, 1948-09-04, p 1, 1949-05-21, p1, # 1949-09-03, p 1, 1950-05-27 p 1, 1950-09-02, p 1, 1951-05-27, p 1, # 1951-09-01, p 1, 1952-05-23, p 1, 1952-09-26, p 1, 1952-12-21, p 8 # # In 1953-1955, the House of Assembly rejected DST each year. [158996], # [162620], [166720] RG, 1953-05-02, p 1, 1954-04-01 p 1, 1955-03-12, p 1 # # 1956: fourth Sunday in May 02:00 to last Sunday in October 02:00 # Time Zone (Seasonal Variation) Act, 1956 (1956: No.44) [1956-05-25] # Bermuda Public Acts 1956, p 331-332 # https://books.google.com/books?id=Xs1AlmD_cEwC&pg=PA63 # # The extension of the Act was rejected by the House of Assembly. [176218] # RG, 1956-12-13, p 1 # # From the Chronological Table of Public and Private Acts up to 1985, it seems # that there does not exist other Acts related to DST before 1973. # https://books.google.com/books?id=r9hMAQAAIAAJ&pg=RA23-PA1 # Public Acts of the Legislature of the Islands of Bermuda, Together with # Statutory Instruments in Force Thereunder, Vol VII # From Dan Jones, reporting in The Royal Gazette (2006-06-26): # Next year, however, clocks in the US will go forward on the second Sunday # in March, until the first Sunday in November. And, after the Time Zone # (Seasonal Variation) Bill 2006 was passed in the House of Assembly on # Friday, the same thing will happen in Bermuda. # http://www.theroyalgazette.com/apps/pbcs.dll/article?AID=/20060529/NEWS/105290135 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Bermuda 1917 only - Apr 5 24:00 1:00 - Rule Bermuda 1917 only - Sep 30 24:00 0 - Rule Bermuda 1918 only - Apr 13 24:00 1:00 - Rule Bermuda 1918 only - Sep 15 24:00 0 S Rule Bermuda 1942 only - Jan 11 2:00 1:00 D Rule Bermuda 1942 only - Oct 18 2:00 0 S Rule Bermuda 1943 only - Mar 21 2:00 1:00 D Rule Bermuda 1943 only - Oct 31 2:00 0 S Rule Bermuda 1944 1945 - Mar Sun>=8 2:00 1:00 D Rule Bermuda 1944 1945 - Nov Sun>=1 2:00 0 S Rule Bermuda 1947 only - May Sun>=15 2:00 1:00 D Rule Bermuda 1947 only - Sep Sun>=8 2:00 0 S Rule Bermuda 1948 1952 - May Sun>=22 2:00 1:00 D Rule Bermuda 1948 1952 - Sep Sun>=1 2:00 0 S Rule Bermuda 1956 only - May Sun>=22 2:00 1:00 D Rule Bermuda 1956 only - Oct lastSun 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] #STDOFF -4:19:18.3 Zone Atlantic/Bermuda -4:19:18 - LMT 1890 # Hamilton -4:19:18 Bermuda BMT/BST 1930 Jan 1 2:00 -4:00 Bermuda A%sT 1974 Apr 28 2:00 -4:00 Canada A%sT 1976 -4:00 US A%sT # Costa Rica # Milne gives -5:36:13.3 as San José mean time. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule CR 1979 1980 - Feb lastSun 0:00 1:00 D Rule CR 1979 1980 - Jun Sun>=1 0:00 0 S Rule CR 1991 1992 - Jan Sat>=15 0:00 1:00 D # IATA SSIM (1991-09) says the following was at 1:00; # go with Shanks & Pottenger. Rule CR 1991 only - Jul 1 0:00 0 S Rule CR 1992 only - Mar 15 0:00 0 S # There are too many San Josés elsewhere, so we'll use 'Costa Rica'. # Zone NAME STDOFF RULES FORMAT [UNTIL] #STDOFF -5:36:13.3 Zone America/Costa_Rica -5:36:13 - LMT 1890 # San José -5:36:13 - SJMT 1921 Jan 15 # San José Mean Time -6:00 CR C%sT # Coco # no information; probably like America/Costa_Rica # Cuba # From Paul Eggert (2013-02-21): # Milne gives -5:28:50.45 for the observatory at Havana, -5:29:23.57 # for the port, and -5:30 for meteorological observations. # For now, stick with Shanks & Pottenger. # From Arthur David Olson (1999-03-29): # The 1999-03-28 exhibition baseball game held in Havana, Cuba, between # the Cuban National Team and the Baltimore Orioles was carried live on # the Orioles Radio Network, including affiliate WTOP in Washington, DC. # During the game, play-by-play announcer Jim Hunter noted that # "We'll be losing two hours of sleep...Cuba switched to Daylight Saving # Time today." (The "two hour" remark referred to losing one hour of # sleep on 1999-03-28 - when the announcers were in Cuba as it switched # to DST - and one more hour on 1999-04-04 - when the announcers will have # returned to Baltimore, which switches on that date.) # From Steffen Thorsen (2013-11-11): # DST start in Cuba in 2004 ... does not follow the same rules as the # years before. The correct date should be Sunday 2004-03-28 00:00 ... # https://web.archive.org/web/20040402060750/http://www.granma.cu/espanol/2004/marzo/sab27/reloj.html # From Evert van der Veer via Steffen Thorsen (2004-10-28): # Cuba is not going back to standard time this year. # From Paul Eggert (2006-03-22): # http://www.granma.cu/ingles/2004/septiembre/juev30/41medid-i.html # says that it's due to a problem at the Antonio Guiteras # thermoelectric plant, and says "This October there will be no return # to normal hours (after daylight saving time)". # For now, let's assume that it's a temporary measure. # From Carlos A. Carnero Delgado (2005-11-12): # This year (just like in 2004-2005) there's no change in time zone # adjustment in Cuba. We will stay in daylight saving time: # http://www.granma.cu/espanol/2005/noviembre/mier9/horario.html # From Jesper Nørgaard Welen (2006-10-21): # An article in GRANMA INTERNACIONAL claims that Cuba will end # the 3 years of permanent DST next weekend, see # http://www.granma.cu/ingles/2006/octubre/lun16/43horario.html # "On Saturday night, October 28 going into Sunday, October 29, at 01:00, # watches should be set back one hour - going back to 00:00 hours - returning # to the normal schedule.... # From Paul Eggert (2007-03-02): # , dated yesterday, # says Cuban clocks will advance at midnight on March 10. # For lack of better information, assume Cuba will use US rules, # except that it switches at midnight standard time as usual. # # From Steffen Thorsen (2007-10-25): # Carlos Alberto Fonseca Arauz informed me that Cuba will end DST one week # earlier - on the last Sunday of October, just like in 2006. # # He supplied these references: # # http://www.prensalatina.com.mx/article.asp?ID=%7B4CC32C1B-A9F7-42FB-8A07-8631AFC923AF%7D&language=ES # http://actualidad.terra.es/sociedad/articulo/cuba_llama_ahorrar_energia_cambio_1957044.htm # # From Alex Krivenyshev (2007-10-25): # Here is also article from Granma (Cuba): # # Regirá el Horario Normal desde el próximo domingo 28 de octubre # http://www.granma.cubaweb.cu/2007/10/24/nacional/artic07.html # # http://www.worldtimezone.com/dst_news/dst_news_cuba03.html # From Arthur David Olson (2008-03-09): # I'm in Maryland which is now observing United States Eastern Daylight # Time. At 9:44 local time I used RealPlayer to listen to # http://media.enet.cu/radioreloj # a Cuban information station, and heard # the time announced as "ocho cuarenta y cuatro" ("eight forty-four"), # indicating that Cuba is still on standard time. # From Steffen Thorsen (2008-03-12): # It seems that Cuba will start DST on Sunday, 2007-03-16... # It was announced yesterday, according to this source (in Spanish): # http://www.nnc.cubaweb.cu/marzo-2008/cien-1-11-3-08.htm # # Some more background information is posted here: # https://www.timeanddate.com/news/time/cuba-starts-dst-march-16.html # # The article also says that Cuba has been observing DST since 1963, # while Shanks (and tzdata) has 1965 as the first date (except in the # 1940's). Many other web pages in Cuba also claim that it has been # observed since 1963, but with the exception of 1970 - an exception # which is not present in tzdata/Shanks. So there is a chance we need to # change some historic records as well. # # One example: # http://www.radiohc.cu/espanol/noticias/mar07/11mar/hor.htm # From Jesper Nørgaard Welen (2008-03-13): # The Cuban time change has just been confirmed on the most authoritative # web site, the Granma. Please check out # http://www.granma.cubaweb.cu/2008/03/13/nacional/artic10.html # # Basically as expected after Steffen Thorsen's information, the change # will take place midnight between Saturday and Sunday. # From Arthur David Olson (2008-03-12): # Assume Sun>=15 (third Sunday) going forward. # From Alexander Krivenyshev (2009-03-04) # According to the Radio Reloj - Cuba will start Daylight Saving Time on # midnight between Saturday, March 07, 2009 and Sunday, March 08, 2009- # not on midnight March 14 / March 15 as previously thought. # # http://www.worldtimezone.com/dst_news/dst_news_cuba05.html # (in Spanish) # From Arthur David Olson (2009-03-09) # I listened over the Internet to # http://media.enet.cu/readioreloj # this morning; when it was 10:05 a. m. here in Bethesda, Maryland the # the time was announced as "diez cinco" - the same time as here, indicating # that has indeed switched to DST. Assume second Sunday from 2009 forward. # From Steffen Thorsen (2011-03-08): # Granma announced that Cuba is going to start DST on 2011-03-20 00:00:00 # this year. Nothing about the end date known so far (if that has # changed at all). # # Source: # http://granma.co.cu/2011/03/08/nacional/artic01.html # # Our info: # https://www.timeanddate.com/news/time/cuba-starts-dst-2011.html # # From Steffen Thorsen (2011-10-30) # Cuba will end DST two weeks later this year. Instead of going back # tonight, it has been delayed to 2011-11-13 at 01:00. # # One source (Spanish) # http://www.radioangulo.cu/noticias/cuba/17105-cuba-restablecera-el-horario-del-meridiano-de-greenwich.html # # Our page: # https://www.timeanddate.com/news/time/cuba-time-changes-2011.html # # From Steffen Thorsen (2012-03-01) # According to Radio Reloj, Cuba will start DST on Midnight between March # 31 and April 1. # # Radio Reloj has the following info (Spanish): # http://www.radioreloj.cu/index.php/noticias-radio-reloj/71-miscelaneas/7529-cuba-aplicara-el-horario-de-verano-desde-el-1-de-abril # # Our info on it: # https://www.timeanddate.com/news/time/cuba-starts-dst-2012.html # From Steffen Thorsen (2012-11-03): # Radio Reloj and many other sources report that Cuba is changing back # to standard time on 2012-11-04: # http://www.radioreloj.cu/index.php/noticias-radio-reloj/36-nacionales/9961-regira-horario-normal-en-cuba-desde-el-domingo-cuatro-de-noviembre # From Paul Eggert (2012-11-03): # For now, assume the future rule is first Sunday in November. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Cuba 1928 only - Jun 10 0:00 1:00 D Rule Cuba 1928 only - Oct 10 0:00 0 S Rule Cuba 1940 1942 - Jun Sun>=1 0:00 1:00 D Rule Cuba 1940 1942 - Sep Sun>=1 0:00 0 S Rule Cuba 1945 1946 - Jun Sun>=1 0:00 1:00 D Rule Cuba 1945 1946 - Sep Sun>=1 0:00 0 S Rule Cuba 1965 only - Jun 1 0:00 1:00 D Rule Cuba 1965 only - Sep 30 0:00 0 S Rule Cuba 1966 only - May 29 0:00 1:00 D Rule Cuba 1966 only - Oct 2 0:00 0 S Rule Cuba 1967 only - Apr 8 0:00 1:00 D Rule Cuba 1967 1968 - Sep Sun>=8 0:00 0 S Rule Cuba 1968 only - Apr 14 0:00 1:00 D Rule Cuba 1969 1977 - Apr lastSun 0:00 1:00 D Rule Cuba 1969 1971 - Oct lastSun 0:00 0 S Rule Cuba 1972 1974 - Oct 8 0:00 0 S Rule Cuba 1975 1977 - Oct lastSun 0:00 0 S Rule Cuba 1978 only - May 7 0:00 1:00 D Rule Cuba 1978 1990 - Oct Sun>=8 0:00 0 S Rule Cuba 1979 1980 - Mar Sun>=15 0:00 1:00 D Rule Cuba 1981 1985 - May Sun>=5 0:00 1:00 D Rule Cuba 1986 1989 - Mar Sun>=14 0:00 1:00 D Rule Cuba 1990 1997 - Apr Sun>=1 0:00 1:00 D Rule Cuba 1991 1995 - Oct Sun>=8 0:00s 0 S Rule Cuba 1996 only - Oct 6 0:00s 0 S Rule Cuba 1997 only - Oct 12 0:00s 0 S Rule Cuba 1998 1999 - Mar lastSun 0:00s 1:00 D Rule Cuba 1998 2003 - Oct lastSun 0:00s 0 S Rule Cuba 2000 2003 - Apr Sun>=1 0:00s 1:00 D Rule Cuba 2004 only - Mar lastSun 0:00s 1:00 D Rule Cuba 2006 2010 - Oct lastSun 0:00s 0 S Rule Cuba 2007 only - Mar Sun>=8 0:00s 1:00 D Rule Cuba 2008 only - Mar Sun>=15 0:00s 1:00 D Rule Cuba 2009 2010 - Mar Sun>=8 0:00s 1:00 D Rule Cuba 2011 only - Mar Sun>=15 0:00s 1:00 D Rule Cuba 2011 only - Nov 13 0:00s 0 S Rule Cuba 2012 only - Apr 1 0:00s 1:00 D Rule Cuba 2012 max - Nov Sun>=1 0:00s 0 S Rule Cuba 2013 max - Mar Sun>=8 0:00s 1:00 D # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Havana -5:29:28 - LMT 1890 -5:29:36 - HMT 1925 Jul 19 12:00 # Havana MT -5:00 Cuba C%sT # Dominican Republic # From Steffen Thorsen (2000-10-30): # Enrique Morales reported to me that the Dominican Republic has changed the # time zone to Eastern Standard Time as of Sunday 29 at 2 am.... # http://www.listin.com.do/antes/261000/republica/princi.html # From Paul Eggert (2000-12-04): # That URL (2000-10-26, in Spanish) says they planned to use US-style DST. # From Rives McDow (2000-12-01): # Dominican Republic changed its mind and presidential decree on Tuesday, # November 28, 2000, with a new decree. On Sunday, December 3 at 1:00 AM the # Dominican Republic will be reverting to 8 hours from the International Date # Line, and will not be using DST in the foreseeable future. The reason they # decided to use DST was to be in synch with Puerto Rico, who was also going # to implement DST. When Puerto Rico didn't implement DST, the president # decided to revert. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule DR 1966 only - Oct 30 0:00 1:00 EDT Rule DR 1967 only - Feb 28 0:00 0 EST Rule DR 1969 1973 - Oct lastSun 0:00 0:30 -0430 Rule DR 1970 only - Feb 21 0:00 0 EST Rule DR 1971 only - Jan 20 0:00 0 EST Rule DR 1972 1974 - Jan 21 0:00 0 EST # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Santo_Domingo -4:39:36 - LMT 1890 -4:40 - SDMT 1933 Apr 1 12:00 # S. Dom. MT -5:00 DR %s 1974 Oct 27 -4:00 - AST 2000 Oct 29 2:00 -5:00 US E%sT 2000 Dec 3 1:00 -4:00 - AST # El Salvador # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Salv 1987 1988 - May Sun>=1 0:00 1:00 D Rule Salv 1987 1988 - Sep lastSun 0:00 0 S # There are too many San Salvadors elsewhere, so use America/El_Salvador # instead of America/San_Salvador. # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/El_Salvador -5:56:48 - LMT 1921 # San Salvador -6:00 Salv C%sT # Guatemala # # From Gwillim Law (2006-04-22), after a heads-up from Oscar van Vlijmen: # Diario Co Latino, at # , # says in an article dated 2006-04-19 that the Guatemalan government had # decided on that date to advance official time by 60 minutes, to lessen the # impact of the elevated cost of oil.... Daylight saving time will last from # 2006-04-29 24:00 (Guatemalan standard time) to 2006-09-30 (time unspecified). # From Paul Eggert (2006-06-22): # The Ministry of Energy and Mines, press release CP-15/2006 # (2006-04-19), says DST ends at 24:00. See # http://www.sieca.org.gt/Sitio_publico/Energeticos/Doc/Medidas/Cambio_Horario_Nac_190406.pdf # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Guat 1973 only - Nov 25 0:00 1:00 D Rule Guat 1974 only - Feb 24 0:00 0 S Rule Guat 1983 only - May 21 0:00 1:00 D Rule Guat 1983 only - Sep 22 0:00 0 S Rule Guat 1991 only - Mar 23 0:00 1:00 D Rule Guat 1991 only - Sep 7 0:00 0 S Rule Guat 2006 only - Apr 30 0:00 1:00 D Rule Guat 2006 only - Oct 1 0:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Guatemala -6:02:04 - LMT 1918 Oct 5 -6:00 Guat C%sT # Haiti # From Gwillim Law (2005-04-15): # Risto O. Nykänen wrote me that Haiti is now on DST. # I searched for confirmation, and I found a press release # on the Web page of the Haitian Consulate in Chicago (2005-03-31), # . Translated from French, it says: # # "The Prime Minister's Communication Office notifies the public in general # and the press in particular that, following a decision of the Interior # Ministry and the Territorial Collectivities [I suppose that means the # provinces], Haiti will move to Eastern Daylight Time in the night from next # Saturday the 2nd to Sunday the 3rd. # # "Consequently, the Prime Minister's Communication Office wishes to inform # the population that the country's clocks will be set forward one hour # starting at midnight. This provision will hold until the last Saturday in # October 2005. # # "Port-au-Prince, March 31, 2005" # # From Steffen Thorsen (2006-04-04): # I have been informed by users that Haiti observes DST this year like # last year, so the current "only" rule for 2005 might be changed to a # "max" rule or to last until 2006. (Who knows if they will observe DST # next year or if they will extend their DST like US/Canada next year). # # I have found this article about it (in French): # http://www.haitipressnetwork.com/news.cfm?articleID=7612 # # The reason seems to be an energy crisis. # From Stephen Colebourne (2007-02-22): # Some IATA info: Haiti won't be having DST in 2007. # From Steffen Thorsen (2012-03-11): # According to several news sources, Haiti will observe DST this year, # apparently using the same start and end date as USA/Canada. # So this means they have already changed their time. # # http://www.alterpresse.org/spip.php?article12510 # http://radiovision2000haiti.net/home/?p=13253 # # From Arthur David Olson (2012-03-11): # The alterpresse.org source seems to show a US-style leap from 2:00 a.m. to # 3:00 a.m. rather than the traditional Haitian jump at midnight. # Assume a US-style fall back as well. # From Steffen Thorsen (2013-03-10): # It appears that Haiti is observing DST this year as well, same rules # as US/Canada. They did it last year as well, and it looks like they # are going to observe DST every year now... # # http://radiovision2000haiti.net/public/haiti-avis-changement-dheure-dimanche/ # http://www.canalplushaiti.net/?p=6714 # From Steffen Thorsen (2016-03-12): # Jean Antoine, editor of www.haiti-reference.com informed us that Haiti # are not going on DST this year. Several other resources confirm this: ... # https://www.radiotelevisioncaraibes.com/presse/heure_d_t_pas_de_changement_d_heure_pr_vu_pour_cet_ann_e.html # https://www.vantbefinfo.com/changement-dheure-pas-pour-haiti/ # http://news.anmwe.com/haiti-lheure-nationale-ne-sera-ni-avancee-ni-reculee-cette-annee/ # From Steffen Thorsen (2017-03-12): # We have received 4 mails from different people telling that Haiti # has started DST again today, and this source seems to confirm that, # I have not been able to find a more authoritative source: # https://www.haitilibre.com/en/news-20319-haiti-notices-time-change-in-haiti.html # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Haiti 1983 only - May 8 0:00 1:00 D Rule Haiti 1984 1987 - Apr lastSun 0:00 1:00 D Rule Haiti 1983 1987 - Oct lastSun 0:00 0 S # Shanks & Pottenger say AT is 2:00, but IATA SSIM (1991/1997) says 1:00s. # Go with IATA. Rule Haiti 1988 1997 - Apr Sun>=1 1:00s 1:00 D Rule Haiti 1988 1997 - Oct lastSun 1:00s 0 S Rule Haiti 2005 2006 - Apr Sun>=1 0:00 1:00 D Rule Haiti 2005 2006 - Oct lastSun 0:00 0 S Rule Haiti 2012 2015 - Mar Sun>=8 2:00 1:00 D Rule Haiti 2012 2015 - Nov Sun>=1 2:00 0 S Rule Haiti 2017 max - Mar Sun>=8 2:00 1:00 D Rule Haiti 2017 max - Nov Sun>=1 2:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Port-au-Prince -4:49:20 - LMT 1890 -4:49 - PPMT 1917 Jan 24 12:00 # P-a-P MT -5:00 Haiti E%sT # Honduras # Shanks & Pottenger say 1921 Jan 1; go with Whitman's more precise Apr 1. # From Paul Eggert (2006-05-05): # worldtimezone.com reports a 2006-05-02 Spanish-language AP article # saying Honduras will start using DST midnight Saturday, effective 4 # months until September. La Tribuna reported today # that Manuel Zelaya, the president # of Honduras, refused to back down on this. # From Jesper Nørgaard Welen (2006-08-08): # It seems that Honduras has returned from DST to standard time this Monday at # 00:00 hours (prolonging Sunday to 25 hours duration). # http://www.worldtimezone.com/dst_news/dst_news_honduras04.html # From Paul Eggert (2006-08-08): # Also see Diario El Heraldo, The country returns to standard time (2006-08-08). # http://www.elheraldo.hn/nota.php?nid=54941&sec=12 # It mentions executive decree 18-2006. # From Steffen Thorsen (2006-08-17): # Honduras will observe DST from 2007 to 2009, exact dates are not # published, I have located this authoritative source: # http://www.presidencia.gob.hn/noticia.aspx?nId=47 # From Steffen Thorsen (2007-03-30): # http://www.laprensahn.com/pais_nota.php?id04962=7386 # So it seems that Honduras will not enter DST this year.... # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Hond 1987 1988 - May Sun>=1 0:00 1:00 D Rule Hond 1987 1988 - Sep lastSun 0:00 0 S Rule Hond 2006 only - May Sun>=1 0:00 1:00 D Rule Hond 2006 only - Aug Mon>=1 0:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Tegucigalpa -5:48:52 - LMT 1921 Apr -6:00 Hond C%sT # # Great Swan I ceded by US to Honduras in 1972 # Jamaica # Shanks & Pottenger give -5:07:12, but Milne records -5:07:10.41 from an # unspecified official document, and says "This time is used throughout the # island". Go with Milne. # # Shanks & Pottenger give April 28 for the 1974 spring-forward transition, but # Lance Neita writes that Prime Minister Michael Manley decreed it January 5. # Assume Neita meant Jan 6 02:00, the same as the US. Neita also writes that # Manley's supporters associated this act with Manley's nickname "Joshua" # (recall that in the Bible the sun stood still at Joshua's request), # and with the Rod of Correction which Manley said he had received from # Haile Selassie, Emperor of Ethiopia. See: # Neita L. The politician in all of us. Jamaica Observer 2014-09-20 # http://www.jamaicaobserver.com/columns/The-politician-in-all-of-us_17573647 # # Zone NAME STDOFF RULES FORMAT [UNTIL] #STDOFF -5:07:10.41 Zone America/Jamaica -5:07:10 - LMT 1890 # Kingston -5:07:10 - KMT 1912 Feb # Kingston Mean Time -5:00 - EST 1974 -5:00 US E%sT 1984 -5:00 - EST # Martinique # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Martinique -4:04:20 - LMT 1890 # Fort-de-France -4:04:20 - FFMT 1911 May # Fort-de-France MT -4:00 - AST 1980 Apr 6 -4:00 1:00 ADT 1980 Sep 28 -4:00 - AST # Nicaragua # # This uses Shanks & Pottenger for times before 2005. # # From Steffen Thorsen (2005-04-12): # I've got reports from 8 different people that Nicaragua just started # DST on Sunday 2005-04-10, in order to save energy because of # expensive petroleum. The exact end date for DST is not yet # announced, only "September" but some sites also say "mid-September". # Some background information is available on the President's official site: # http://www.presidencia.gob.ni/Presidencia/Files_index/Secretaria/Notas%20de%20Prensa/Presidente/2005/ABRIL/Gobierno-de-nicaragua-adelanta-hora-oficial-06abril.htm # The Decree, no 23-2005 is available here: # http://www.presidencia.gob.ni/buscador_gaceta/BD/DECRETOS/2005/Decreto%2023-2005%20Se%20adelanta%20en%20una%20hora%20en%20todo%20el%20territorio%20nacional%20apartir%20de%20las%2024horas%20del%2009%20de%20Abril.pdf # # From Paul Eggert (2005-05-01): # The decree doesn't say anything about daylight saving, but for now let's # assume that it is daylight saving.... # # From Gwillim Law (2005-04-21): # The Associated Press story on the time change, which can be found at # http://www.lapalmainteractivo.com/guias/content/gen/ap/America_Latina/AMC_GEN_NICARAGUA_HORA.html # and elsewhere, says (fifth paragraph, translated from Spanish): "The last # time that a change of clocks was applied to save energy was in the year 2000 # during the Arnoldo Alemán administration."... # The northamerica file says that Nicaragua has been on UTC-6 continuously # since December 1998. I wasn't able to find any details of Nicaraguan time # changes in 2000. Perhaps a note could be added to the northamerica file, to # the effect that we have indirect evidence that DST was observed in 2000. # # From Jesper Nørgaard Welen (2005-11-02): # Nicaragua left DST the 2005-10-02 at 00:00 (local time). # http://www.presidencia.gob.ni/presidencia/files_index/secretaria/comunicados/2005/septiembre/26septiembre-cambio-hora.htm # (2005-09-26) # # From Jesper Nørgaard Welen (2006-05-05): # http://www.elnuevodiario.com.ni/2006/05/01/nacionales/18410 # (my informal translation) # By order of the president of the republic, Enrique Bolaños, Nicaragua # advanced by sixty minutes their official time, yesterday at 2 in the # morning, and will stay that way until 30th of September. # # From Jesper Nørgaard Welen (2006-09-30): # http://www.presidencia.gob.ni/buscador_gaceta/BD/DECRETOS/2006/D-063-2006P-PRN-Cambio-Hora.pdf # My informal translation runs: # The natural sun time is restored in all the national territory, in that the # time is returned one hour at 01:00 am of October 1 of 2006. # # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Nic 1979 1980 - Mar Sun>=16 0:00 1:00 D Rule Nic 1979 1980 - Jun Mon>=23 0:00 0 S Rule Nic 2005 only - Apr 10 0:00 1:00 D Rule Nic 2005 only - Oct Sun>=1 0:00 0 S Rule Nic 2006 only - Apr 30 2:00 1:00 D Rule Nic 2006 only - Oct Sun>=1 1:00 0 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Managua -5:45:08 - LMT 1890 -5:45:12 - MMT 1934 Jun 23 # Managua Mean Time? -6:00 - CST 1973 May -5:00 - EST 1975 Feb 16 -6:00 Nic C%sT 1992 Jan 1 4:00 -5:00 - EST 1992 Sep 24 -6:00 - CST 1993 -5:00 - EST 1997 -6:00 Nic C%sT # Cayman Is # Panama # # Atikokan and Coral Harbour, Canada, match Panama since 1970. # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Panama -5:18:08 - LMT 1890 -5:19:36 - CMT 1908 Apr 22 # Colón Mean Time -5:00 - EST # Anguilla # Antigua & Barbuda # Aruba # Caribbean Netherlands # Curaçao # Dominica # Grenada # Guadeloupe # Montserrat # Puerto Rico # St Barthélemy # St Kitts-Nevis # Sint Maarten / St Martin # St Lucia # St Vincent & the Grenadines # Trinidad & Tobago # Virgin Is (UK & US) # # There are too many San Juans elsewhere, so we'll use 'Puerto_Rico'. # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Puerto_Rico -4:24:25 - LMT 1899 Mar 28 12:00 # San Juan -4:00 - AST 1942 May 3 -4:00 US A%sT 1946 -4:00 - AST # St Pierre and Miquelon # There are too many St Pierres elsewhere, so we'll use 'Miquelon'. # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Miquelon -3:44:40 - LMT 1911 May 15 # St Pierre -4:00 - AST 1980 May -3:00 - -03 1987 -3:00 Canada -03/-02 # Turks and Caicos # # From Chris Dunn in # https://bugs.debian.org/415007 # (2007-03-15): In the Turks & Caicos Islands (America/Grand_Turk) the # daylight saving dates for time changes have been adjusted to match # the recent U.S. change of dates. # # From Brian Inglis (2007-04-28): # http://www.turksandcaicos.tc/calendar/index.htm [2007-04-26] # there is an entry for Nov 4 "Daylight Savings Time Ends 2007" and three # rows before that there is an out of date entry for Oct: # "Eastern Standard Times Begins 2007 # Clocks are set back one hour at 2:00 a.m. local Daylight Saving Time" # indicating that the normal ET rules are followed. # From Paul Eggert (2014-08-19): # The 2014-08-13 Cabinet meeting decided to stay on UT -04 year-round. See: # http://tcweeklynews.com/daylight-savings-time-to-be-maintained-p5353-127.htm # Model this as a switch from EST/EDT to AST ... # From Chris Walton (2014-11-04): # ... the TCI government appears to have delayed the switch to # "permanent daylight saving time" by one year.... # http://tcweeklynews.com/time-change-to-go-ahead-this-november-p5437-127.htm # # From the Turks & Caicos Cabinet (2017-07-20), heads-up from Steffen Thorsen: # ... agreed to the reintroduction in TCI of Daylight Saving Time (DST) # during the summer months and Standard Time, also known as Local # Time, during the winter months with effect from April 2018 ... # https://www.gov.uk/government/news/turks-and-caicos-post-cabinet-meeting-statement--3 # From Paul Eggert (2017-08-26): # The date of effect of the spring 2018 change appears to be March 11, # which makes more sense. See: Hamilton D. Time change back # by March 2018 for TCI. Magnetic Media. 2017-08-25. # http://magneticmediatv.com/2017/08/time-change-back-by-march-2018-for-tci/ # # From P Chan (2020-11-27): # Standard Time Declaration Order 2015 (L.N. 15/2015) # http://online.fliphtml5.com/fizd/czin/#p=2 # # Standard Time Declaration Order 2017 (L.N. 31/2017) # http://online.fliphtml5.com/fizd/dmcu/#p=2 # # From Tim Parenti (2020-12-05): # Although L.N. 31/2017 reads that it "shall come into operation at 2:00 a.m. # on 11th March 2018", a precise interpretation here poses some problems. The # order states that "the standard time to be observed throughout the Turks and # Caicos Islands shall be the same time zone as the Eastern United States of # America" and further clarifies "[f]or the avoidance of doubt" that it # "applies to the Eastern Standard Time as well as any changes thereto for # Daylight Saving Time." However, as clocks in Turks and Caicos approached # 02:00 -04, and thus the declared implementation time, it was still 01:00 EST # (-05), as DST in the Eastern US would not start until an hour later. # # Since it is unlikely that those on the islands switched their clocks twice in # the span of an hour, we assume instead that the adoption of EDT actually took # effect once clocks in the Eastern US had sprung forward, from 03:00 -04. # This discrepancy only affects the time zone abbreviation and DST flag for the # intervening hour, not wall clock times, as -04 was maintained throughout. # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Grand_Turk -4:44:32 - LMT 1890 #STDOFF -5:07:10.41 -5:07:10 - KMT 1912 Feb # Kingston Mean Time -5:00 - EST 1979 -5:00 US E%sT 2015 Mar 8 2:00 -4:00 - AST 2018 Mar 11 3:00 -5:00 US E%sT # Local Variables: # coding: utf-8 # End: