Mountain Time Zone

Last updated
Mountain Time Zone
Time zone
Timezoneswest.PNG
  Mountain Time Zone
UTC offset
MST UTC−07:00
MDT UTC−06:00
Current time
04:35, September 28, 2021 MST [refresh]
05:35, September 28, 2021 MDT [refresh]
Observance of DST
DST is observed in some of this time zone.

The Mountain Time Zone of North America keeps time by subtracting seven hours from Coordinated Universal Time (UTC) when standard time (UTC−07:00) is in effect, and by subtracting six hours during daylight saving time (UTC−06:00). The clock time in this zone is based on the mean solar time at the 105th meridian west of the Greenwich Observatory. In the United States, the exact specification for the location of time zones and the dividing lines between zones is set forth in the Code of Federal Regulations at 49 CFR 71. [lower-alpha 1]

Contents

In the United States and Canada, this time zone is generically called Mountain Time (MT). Specifically, it is Mountain Standard Time (MST) when observing standard time, and Mountain Daylight Time (MDT) when observing daylight saving time. The term refers to the Rocky Mountains, which range from British Columbia to New Mexico. In Mexico, this time zone is known as the tiempo de la montaña or zona Pacífico ("Pacific Zone"). In the US and Canada, the Mountain Time Zone is to the east of the Pacific Time Zone and to the west of the Central Time Zone.

In some areas, starting in 2007, the local time changes from MST to MDT at 2 am MST to 3 am MDT on the second Sunday in March and returns at 2 am MDT to 1 am MST on the first Sunday in November.

Sonora in Mexico and most of Arizona in the United States do not observe daylight saving time, and during the spring, summer, and autumn months they are on the same time as Pacific Daylight Time. [4] The Navajo Nation, most of which lies within Arizona but extends into Utah and New Mexico (which do observe DST), does observe DST, although the Hopi Reservation, as well as some Arizona state offices lying within the Navajo Nation, do not.

The largest city in the Mountain Time Zone is Phoenix, Arizona; the Phoenix metropolitan area is the largest metropolitan area in the zone.

Canada

Only one Canadian province is fully contained in the Mountain Time Zone:

One province and one territory are split between the Mountain Time Zone and the Pacific Time Zone:

One territory and one province are split between the Mountain Time Zone and the Central Time Zone

On September 24, 2020, Yukon switched to the Mountain Standard Time year-round. Therefore clocks in Yukon and Alberta are the same in the winter, and Alberta is one hour ahead in summer. Previously the territory had used the Pacific Time Zone with daylight saving time: UTC−8 in winter and UTC−7 in summer. [5]

Mexico

The following states have the same time as Mountain Time Zone:

United States

Six states are fully contained in the Mountain Time Zone:

Two states are split between the Mountain Time Zone and the Pacific Time Zone. The following locations observe Mountain Time:

Five states are split between the Mountain Time Zone and the Central Time Zone. The following locations observe Mountain Time:

Major metropolitan areas

The following is a list of major cities located within the Mountain Time Zone, ordered alphabetically.

See also

Notes

  1. The specification for the Mountain Time Zone in the United States is set forth at 49 CFR 71.8. [1] The boundary between Central and Mountain time zones is set forth at 49 CFR 71.7, [2] and the boundary between Mountain and Pacific time zones is set forth at 49 CFR 71.9. [3]

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Pacific Time Zone North American time zone

The Pacific Time Zone (PT) is a time zone encompassing parts of western Canada, the western United States, and western Mexico. Places in this zone observe standard time by subtracting eight hours from Coordinated Universal Time (UTC−08:00). During daylight saving time, a time offset of UTC−07:00 is used.

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UTC−05:00 Identifier for a time offset from UTC of −5

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UTC−07:00 Identifier for a time offset from UTC of −7

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UTC−06:00 Identifier for a time offset from UTC of −6

UTC−06:00 is an identifier for a time offset from UTC of −06:00. In North America, it is observed in the Central Time Zone during standard time, and in the Mountain Time Zone during the other eight months. Several Latin American countries and a few other places use it year-round.

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Time in Mexico Overview about the time zones in Mexico

Mexico uses four main time zones since February 2015. Most of the country observes Daylight Saving Time (DST).

  1. Zona Sureste covers the state of Quintana Roo is UTC-05:00 year round. It is the equivalent of U.S. Eastern Standard Time.
  2. Zona Centro covers the eastern three-fourths of Mexico, including Mexico City, Guadalajara, and Monterrey. For most of the year, it is the equivalent of U.S. Central Time.
  3. Zona Pacífico covers the states of Baja California Sur, Chihuahua, Nayarit, Sinaloa, and Sonora. For most of the year, it is the equivalent of U.S. Mountain Time. The state of Sonora, like the adjacent U.S. state of Arizona, does not observe DST.
  4. Zona Noroeste covers the state of Baja California. It is identical to U.S. Pacific Time, including the DST schedule.
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Milner, Colorado Unincorporated community in Colorado, United States

Milner is an unincorporated community located in Routt County, Colorado, United States. The elevation is 6,522 feet above sea level. Milner lies in the Mountain Time Zone (MST/MDT) and observes daylight saving time. The settlement is located along U.S. Hwy 40 between the nearby communities of Craig and Steamboat Springs.

Mexico adopted daylight saving time nationwide in 1996, even in its tropical regions, because of its increasing economic ties to the United States. Although the United States changed the schedule for DST beginning in 2007, only the municipalities located less than 20 km from the border have adopted the change. Daylight saving time for Mexico begins the first Sunday of April and ends last Sunday of October; and is usually referred to as the "Summer Schedule".

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.

Coalwood, Montana Unincorporated community in Montana, United States

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References

  1. "49 CFR 71.8 Mountain zone". Code of Federal Regulations . Retrieved October 7, 2011.
  2. "49 CFR 71.7 Boundary line between central and mountain zones". Code of Federal Regulations. Retrieved October 7, 2011.
  3. "49 CFR 71.9 Boundary line between mountain and Pacific zones". Code of Federal Regulations. Retrieved October 7, 2011.
  4. Robbins, Ted (March 11, 2007). "Arizona Says No to Daylight-Saving Time". Weekend Edition Sunday . National Public Radio . Retrieved June 18, 2012.
  5. http://www.gov.yk.ca/legislation/regs/oic2020_125.pdf