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The United States Virgin Islands use the Atlantic Time Zonewith no daylight saving time, due to how close it is to the equator. This is also true in Puerto Rico.
A time zone is an area that observes a uniform standard time for legal, commercial and social purposes. Time zones tend to follow the boundaries between countries and their subdivisions instead of strictly following longitude, because it is convenient for areas in frequent communication to keep the same time.
Territories of the United States are sub-national administrative divisions overseen by the United States government. The various U.S. territories differ from the U.S. states and Native American tribes in that they are not sovereign entities. In contrast, each state has a sovereignty separate from that of the federal government and each federally-recognized Native American tribe possesses limited tribal sovereignty as a "dependent sovereign nation". Territories are classified by incorporation and whether they have an "organized" government through an organic act passed by the Congress. U.S. territories are under U.S. sovereignty and, consequently, may be treated as part of the United States proper in some ways and not others. Unincorporated territories in particular are not considered to be integral parts of the United States, and the Constitution of the United States applies only partially in those territories.
The Hawaii–Aleutian Time Zone observes Hawaii–Aleutian Standard Time (HST), by subtracting ten hours from Coordinated Universal Time (UTC−10:00). The clock time in this zone is based on the mean solar time of the 150th meridian west of the Greenwich Observatory.
Central European Time (CET), used in most parts of Europe and a few North African countries, is a standard time which is 1 hour ahead of Coordinated Universal Time (UTC). The time offset from UTC can be written as UTC+01:00. The same standard time, UTC+01:00, is also known as Middle European Time and under other names like Berlin Time, Warsaw Time, Paris Time or Rome Time.
Western European Time is a time zone covering parts of western Europe and consists of countries using UTC±00:00. It is one of the three standard time zones in the European Union along with Central European Time and Eastern European Time.
Time in the United States, by law, is divided into nine standard time zones covering the states, territories and other US possessions, with most of the United States observing daylight saving time (DST) for approximately the spring, summer, and fall months. The time zone boundaries and DST observance are regulated by the Department of Transportation. Official and highly precise timekeeping services (clocks) are provided by two federal agencies: the National Institute of Standards and Technology (NIST) ; and the United States Naval Observatory (USNO). The clocks run by these services are kept synchronized with each other as well as with those of other international timekeeping organizations.
Summer time in Europe is the variation of standard clock time that is applied in most European countries in the period between spring and autumn, during which clocks are advanced by one hour from the time observed in the rest of the year, with a view to making the most efficient use of seasonal daylight. It corresponds to the notion and practice of daylight saving time (DST) to be found in many other parts of the world.
Central European Summer Time (CEST), sometimes referred to as Central European Daylight Time (CEDT), is the standard clock time observed during the period of summer daylight-saving in those European countries which observe Central European Time during the other part of the year. It corresponds to UTC+02:00, which makes it the same as Eastern European Time, Central Africa Time, South African Standard Time, Egypt Standard Time and Kaliningrad Time in Russia.
The Atlantic Time Zone is a geographical region that keeps standard time—called Atlantic Standard Time (AST)—by subtracting four hours from Coordinated Universal Time (UTC), resulting in UTC−04:00. During part of the year, some portions of the zone observe daylight saving time, referred to as Atlantic Daylight Time (ADT), by moving their clocks forward one hour to result in UTC−03:00. The clock time in this zone is based on the mean solar time of the 60th meridian west of the Greenwich Observatory.
UTC−04:00 is an identifier for a time offset from UTC of −04:00. It is observed in the Eastern Time Zone during the warm months of daylight saving time, as Eastern Daylight Time. The Atlantic Time Zone observes it during standard time . It is observed all year in the Eastern Caribbean.
UTC+03:00 is an identifier for a time offset from UTC of +03:00. In areas using this time offset, the time is three hours later than the Coordinated Universal Time (UTC). Following the ISO 8601 standard, a time with this offset would be written as, for example, 2019-02-08T23:36:06+03:00.
There are eleven time zones in Russia, which currently observe times ranging from UTC+02:00 to UTC+12:00. Daylight saving time (DST) is not used in Russia since 26 October 2014. From 27 March 2011 to 26 October 2014, permanent DST was used.
Daylight saving time in the United States is the practice of setting the clock forward by one hour when there is longer daylight during day, so that evenings have more daylight and mornings have less. Most areas of the United States and Canada observe daylight saving time (DST), the exceptions being Arizona, Hawaii, and the overseas territories of American Samoa, Guam, the Northern Mariana Islands, Puerto Rico, and the United States Virgin Islands. The Uniform Time Act of 1966 established the system of uniform daylight saving time throughout the US.
Zambee is a settlement on the island of Saint Thomas in the United States Virgin Islands.
Samoa uses UTC+13:00 as standard time and UTC+14:00 as daylight saving time, which it observes during summer in the Southern Hemisphere. In 2011, daylight saving time ended on Saturday, 2 April 2011, 04:00 local daylight time and started on Saturday, 24 September 2011, 03:00 local standard time. Because it is located near the equator, Samoa traditionally did not observe daylight saving time. The introduction of daylight saving time was initially planned for 2009 but was postponed for one year in the aftermath of the 2009 Samoa tsunami.
Daylight saving time in the Americas is the arrangement in the Americas by which clocks are advanced by one hour in spring and moved back in autumn, to make the most of seasonal daylight. The practice is widespread in North America, with most of Canada, Mexico, and the United States of America participating, but much less so in South America.
Most areas in Europe and North America observe daylight saving time (DST), whereas most areas of Africa and Asia do not. In South America, most countries in the north of the continent near the Equator do not observe DST, whereas Paraguay and most of Chile do. The practice of observing daylight saving time in Oceania is also mixed, with New Zealand and parts of southeastern Australia observing DST, while most other areas do not.
Time in Arizona, as in all U.S. states, is regulated by the United States Department of Transportation as well as by state and tribal law.
Puerto Rico uses Atlantic Standard Time throughout the year, with no Daylight Saving Time, due to how close it is to the Equator. This is also true in the United States Virgin Islands. Hence, during the summer, clocks in Puerto Rico match those in New York City and Miami, while during the winter clocks on the island match those in Bermuda.