Central Time Zone (North America)

     CST or UTC−6

The Central Time Zone is in North America and observes standard time by subtracting six hours from UTC during standard time (UTC−06) and five hours during daylight saving time (UTC−05). The clock time in this zone, composed almost totally of a strip of territory in North America, is based on the mean solar time of the 90th meridian west of the Greenwich Observatory.

In the United States and Canada, this time zone is generically called Central Time (CT). Specifically, it is Central Standard Time (CST) when observing standard time (winter), and Central Daylight Time (CDT) when observing daylight saving (summer). In Mexico this time is known as the Tiempo del Centro (Center Time).

The zone is two hours ahead of the Pacific Time Zone, one hour ahead of the Mountain Time Zone, and one hour behind the Eastern Time Zone.

Contents

Regions using Central Standard Time

Canada

The Canadian province that observes Central Time in its entirety:

The Canadian provinces and territories that observe Central Time in part with another time zone (other time zone):

United States

The states of the United States that observe Central Time in their entirety:

  • Alabama
    • Although the entire state of Alabama is legally on Central Time, Phenix City and its surrounding area unofficially observe Eastern Time, as Phenix City is part of the media market and metropolitan area of the considerably larger city of Columbus, Georgia.
  • Arkansas
  • Illinois
  • Iowa
  • Louisiana
  • Minnesota
  • Mississippi
  • Missouri
  • Oklahoma
    • Although the entire state of Oklahoma is legally on Central Time, the unincorporated community of Kenton, at the extreme western end of the Panhandle, unofficially observes Mountain Time.
  • Wisconsin

The states of the United States that observe Central Time only in part with another time zone:

Part in Mountain Time

Part in Eastern Time

The exact specification for the location of time zones and the dividing line between zones is set forth in the Code of Federal Regulations at 49 CFR 71.[1]

Mexico

Most of Mexico belongs to the Central Time Zone, with the six northwestern-most states being the exception: Baja California Sur, Chihuahua, Nayarit, Sinaloa, and Sonora follow UTC−7, while Baja California follows UTC−8.

The states of Mexico that observe Central Time in their entirety:

The states of the Mexico that observe Central Time only in part with another time zone (other time zone).

Central Daylight Time

Daylight saving time is in effect in much of the time zone between mid-March and early November. The modified time is called Central Daylight Time (CDT) and is UTC−5. Saskatchewan, Sonora and Galápagos do not observe the change, remaining on Standard Time year round. One reason that Saskatchewan does not take part in the time change is that geographically, most of the province should be placed in the Mountain Time Zone. To avoid this, they have moved onto "permanent" daylight saving by being part of the Central Time Zone. The only exception is the region immediately surrounding the Saskatchewan side of the biprovincial city of Lloydminster, which has chosen to use Mountain Time with DST, synchronizing its clocks with those of Alberta.

In some areas, starting in 2007, the local time changes from CST to CDT at 02:00 LST to 03:00 LDT on the second Sunday in March and returns at 02:00 LDT to 01:00 LST on the first Sunday in November. Mexico decided not to go along with this change and observes DST from the first Sunday in April to the last Sunday in October.

Alphabetical list of cities and metropolitan areas

See also

References

  1. The specification for the Central Time Zone is set forth at 49 CFR 71.6, and is listed in Text and pdf formats.
    The boundary between Eastern and Central is set forth at 49 CFR 71.5, and is listed in text and pdf formats.The boundary between Central and Mountain is set forth at 49 CFR 71.7, and is listed in text and pdf formats.

Sources