Where are the boundaries for the Mountain and the Central time zones?

Answer 1

From north to south the Mountain-Central time zone boundaries is as follows:

Beginning at the North Pole it runs south along 97.5° West Longitude.

NORTHWEST TERRITORIES

The line bisects the Northwest Territories even with the Saskatchewan/Manitoba border to the Northwest Territories' southern border.

The time zone line then goes west along the Saskatchewan-Northwest Territory border to the Saskatchewan-Alberta. border.

SASKATCHEWAN-ALBERTA

The time zone line then goes south along the Saskatchewan-Alberta Border to the US-Canada border.

(Saskatchewan DOES NOT observe Daylight Saving time. It is in Central Standard time year-round)

NORTH DAKOTA

The time zone line goes EAST along the US-Canada border to the North Dakota-Montana border.

The time zone line then follows the North Dakota-Montana border south until it reaches McKenzie County North Dakota.

The time zone line bisects McKenzie Co. along the northern border of the Little Missouri National Grasslands to the Dunn County Line.

The time zone line then follows the Dunn County border along the Dunn Co. north and east borders to Mercer Co.

The time zone line wraps around of Mercer County until it reaches Morton County.

The time zone line then goes East to the Missouri River (Morton County's Western Border) into South Dakota.

SOUTH DAKOTA

The time zone line follows the Missouri River down into South Dakota along the Eastern border of Sioux Co. ND, Carson SD, Dewey SD, and Stanley SD counties.

The Time Zone Line then goes west along the Stanley-Lyman Co line then turns south along the Jones-Lyman Co line and along the western border of Tripp Co. SD into Kansas.

NEBRASKA

The line goes WEST along the SD-NE border then turns south bisecting Cherry Co, NE. in a line running north-south at about the same longitude as the Hooker-Thomas county line, then continues south along the county Hooker-Thomas County line and then McPherson-Logan county line to Lincoln County.

The time zone line wraps along the north and WEST borders of Lincoln CO going south along the Chase-Hayes and Dundee-Hitchcock county lines to Kansas

KANSAS

The Mountain-Central time zone line goes WEST along the Kansas-Nebraska Border to the Colorado Border. It goes south following the Colorado-Kansas border and turns EAST wrapping around Cheyenne Co Kansas.

It then turns south again along the eastern borders of Sherman, Wallace Greeley and Hamilton Counties. It then goes WEST again along the southern border of Hamilton County to the Kansas-Colorado Border.

The time zone line then goes south along the Colorado Kansas border to the Oklahoma border.

OKLAHOMA-COLORADO

The time zone line goes WEST along the Oklahoma-Colorado border until it reaches the New Mexico Border.

NEW MEXICO-TEXAS

The mountain-central time zone line goes south along the New Mexico-Oklahoma and New Mexico-Texas state lines.

TEXAS

It wraps around the southern side of New Mexico following the Texas Border westward until it reaches the Hudspeth-Culberson County Line in Texas were it turns south to the US-Mexico border.

US-MEXICO

The time zone line goes EAST and SOUTH along the US-Mexico Border all the border between the Mexican states of Chihuahua and Coahuila. (Across the Rio Grande from Big Bend National Park)

MEXICO

The Mountain-Central time zone line turns south along the Chihuahua and Coahuila state line. It continues to wrap around Chihuahua along the Chihuahua-Durango State line to the Sineloa state line. It continues south along the Sineloa-Durango state line a Then goes along the eastern and southern border of Nayarit out to the Pacific Ocean

PACIFIC OCEAN (At this point Mountain time just is GMT-7 and Central is GMT-6)

The time zone goes along Mexico's Western and southern Coast to 97.5° W Longitude. The time zone delineation then goes directly south along 97.5° W Longitude

EASTER ISLAND

The time zone delineation turns due west at about the 25° S Latitude line to about 111.5° W Longitude. Then turns south to the 29° S Latitude line and back East to the 97.5° W Longitude line. This forms a box wrapping around Easter Island to keep it at GMT-6 instead of where it should be at GMT-7

ANTACTICA

The time zone delineation follows the 97.5° W Longitude line to Antarctica where the time zone ceases to exist. There is no GMT-7 in Antarctica.

Answer 2

The boundary between the Mountain and Central time zones runs through several U.S. states, including Montana, Wyoming, North Dakota, South Dakota, Nebraska, Kansas, Texas, and Oklahoma. In these states, the boundary is generally determined by the 105th meridian west for Mountain Time and the 90th meridian west for Central Time.