The Hawaii–Aleutian Time Zone observes Hawaii–Aleutian Standard Time (HST) by subtracting ten hours from

Coordinated Universal Time Coordinated Universal Time or UTC is the primary time standard by which the world regulates clocks and time. It is within about one second of Solar time#Mean solar time, mean solar time (such as Universal Time, UT1) at 0° longitude (at the I ...

( UTC−10:00). The clock time in this zone is based on the

mean solar time Solar time is a calculation of the passage of time based on the position of the Sun in the sky. The fundamental unit of solar time is the day, based on the synodic rotation period. Two types of solar time are apparent solar time ( sundia ...

of the 150th meridian west of the Greenwich Observatory. The zone takes its name from the two areas it includes:

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only stat ...

and the portion of

Alaska Alaska ( ; russian: Аляска, Alyaska; ale, Alax̂sxax̂; ; ems, Alas'kaaq; Yup'ik: ''Alaskaq''; tli, Anáaski) is a state located in the Western United States on the northwest extremity of North America. A semi-exclave of the U ...

Aleutian Islands The Aleutian Islands (; ; ale, Unangam Tanangin,”Land of the Aleuts", possibly from Chukchi ''aliat'', "island"), also called the Aleut Islands or Aleutic Islands and known before 1867 as the Catherine Archipelago, are a chain of 14 large v ...

west of 169° 30′ W longitude. During

daylight saving time Daylight saving time (DST), also referred to as daylight savings time or simply daylight time (United States, Canada, and Australia), and summer time (United Kingdom, European Union, and others), is the practice of advancing clocks (typicall ...

(DST), the Alaskan portion observes Hawaii–Aleutian Daylight Time (HDT, UTC−09:00), while Hawaii stays on standard time. Hawaii has not observed daylight saving time since September 1945. From 1900 until 1947, UTC−10:30 was used as

standard time Standard time is the synchronisation of clocks within a geographical region to a single time standard, rather than a local mean time standard. Generally, standard time agrees with the local mean time at some meridian that passes through the ...

in Hawaii.

French Polynesia )Territorial motto: ( en, "Great Tahiti of the Golden Haze") , anthem = , song_type = Regional anthem , song = "Ia Ora 'O Tahiti Nui" , image_map = French Polynesia on the globe (French Polynesia centered).svg , map_alt = Location of French ...

uses UTC−10:00 for its major cities. The

Cook Islands ) , image_map = Cook Islands on the globe (small islands magnified) (Polynesia centered).svg , capital = Avarua , coordinates = , largest_city = Avarua , official_languages = , lan ...

also use the same time. These areas do not use DST. "Hawaii–Aleutian Time Zone" is a U.S. term and for that reason the Polynesian areas are not considered to be a part of the Hawaii–Aleutian Time Zone. The largest city and metropolitan area in the Hawaii–Aleutian Time Zone are Honolulu and its metropolitan area, respectively.

Major metropolitan areas

Honolulu, Hawaii Honolulu (; ) is the capital and largest city of the U.S. state of Hawaii, which is in the Pacific Ocean. It is an unincorporated county seat of the consolidated City and County of Honolulu, situated along the southeast coast of the island ...

Hilo, Hawaii Hilo () is a census-designated place (CDP) and the largest settlement in Hawaii County, Hawaii, United States, which encompasses the Island of Hawaii. The population was 44,186 according to the 2020 census. It is the fourth-largest settlement ...

* Kahului, Hawaii *

Kailua-Kona, Hawaii Kailua-Kona is an unincorporated community and census-designated place (CDP) in Hawaii County, Hawaii, United States. It is also known as Kailua (a name it shares with a community located on the windward side of Oahu), as Kona (a name it share ...

* Kapaa, Hawaii

Other significant places

Adak Island, Alaska Adak Island ( ale, Adaax, russian: Адак) or Father Island is an island near the western extent of the Andreanof Islands group of the Aleutian Islands in Alaska. Alaska's southernmost town, Adak, is located on the island. The island has a la ...

Johnston Atoll Johnston Atoll is an unincorporated territory of the United States, currently administered by the United States Fish and Wildlife Service (USFWS). Johnston Atoll is a National Wildlife Refuge and part of the Pacific Remote Islands Marine Nati ...

References

External links

HST – Hawaii–Aleutian Standard TimeThe official U.S. time for the Hawaii–Aleutian time zone (Hawaii)
''dead link''
The official U.S. time for the Hawaii–Aleutian time zone (Aleutian Islands)
''dead link''
What are the time zones in the United States? (NIST)Hawaiian-Aleutian zone at Cornell
Time zones Time zones in the United States {{Hawaii-stub

Major metropolitan areas

Other significant places

See also

References

External links