Wyoming

Wyoming  is a state in the mountain region of the Western United States. The state is the ninth largest by area, but the least populous and the second least densely populated of the 50 United States. The western two-thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High Plains. Cheyenne is the capital and the most populous city in Wyoming, with a population estimate of 62,448 in 2013.

Geography

A back county road in the Sierra Madre Range of southeastern Wyoming near Bridger Peak.

As specified in the designating legislation for the Territory of Wyoming, Wyoming’s borders are lines of latitude, 41°N and 45°N, and longitude, 104°3’W and 111°3’W (27° W and 34° W of the Washington Meridian), making the shape of the state a latitude-longitude quadrangle. Wyoming is one of only three states (along with Colorado and Utah) to have borders along only straight latitudinal and longitudinal lines, rather than being defined by natural landmarks. Due to surveying inaccuracies during the 19th century, Wyoming’s legal border deviates from the true latitude and longitude lines by up to half of a mile (0.8 km) in some spots, especially in the mountainous region along the 45th parallel. Wyoming is bordered on the north by Montana, on the east by South Dakota and Nebraska, on the south by Colorado, on the southwest by Utah, and on the west by Idaho. It is the ninth largest state in the United States in total area, containing 97,814 square miles (253,340 km²) and is made up of 23 counties. From the north border to the south border it is 276 miles (444 km); and from the east to the west border is 365 miles (587 km) at its south end and 342 miles (550 km) at the north end.

Mountain Ranges

The Great Plains meet the Rocky Mountains in Wyoming. The state is a great plateau broken by many mountain ranges. Surface elevations range from the summit of Gannett Peak in the Wind River Mountain Range, at 13,804 feet (4,207 m), to the Belle Fourche River valley in the state’s northeast corner, at 3,125 feet (952 m). In the northwest are the Absaroka, Owl Creek, Gros Ventre, Wind River and the Teton ranges. In the north central are the Big Horn Mountains; in the northeast, the Black Hills; and in the southern region the Laramie, Snowy and Sierra Madre ranges.

The Snowy Range in the south central part of the state is an extension of the Colorado Rockies in both geology and appearance. The Wind River Range in the west central part of the state is remote and includes more than 40 mountain peaks in excess of 13,000 ft (4,000 m) tall in addition to Gannett Peak, the highest peak in the state. The Big Horn Mountains in the north central portion are somewhat isolated from the bulk of the Rocky Mountains.

Wyoming terrain

The Teton Range in the northwest extends for 50 miles (80 km), part of which is included in Grand Teton National Park. The park includes the Grand Teton, the second highest peak in the state.

The Continental Divide spans north-south across the central portion of the state. Rivers east of the divide drain into the Missouri River Basin and eventually the Gulf of Mexico. They are the North Platte, Wind, Big Horn and the Yellowstone rivers. The Snake River in northwest Wyoming eventually drains into the Columbia River and the Pacific Ocean, as does the Green River through the Colorado River Basin.

The Continental Divide forks in the south central part of the state in an area known as the Great Divide Basin where the waters that flow or precipitate into this area remain there and cannot flow to any ocean. Instead, because of the overall aridity of Wyoming, water in the Great Divide Basin simply sinks into the soil or evaporates.

Several rivers begin in or flow through the state, including the Yellowstone River, Bighorn River, Green River, and the Snake River.

Climate

Wyoming’s climate is generally semi-arid and continental (Köppen climate classification BSk), and is drier and windier in comparison to most of the United States with greater temperature extremes. Much of this is due to the topography of the state. Summers in Wyoming are warm with July high temperatures averaging between 85 and 95 °F (29 and 35 °C) in most of the state. With increasing elevation, however, this average drops rapidly with locations above 9,000 feet (2,700 m) averaging around 70 °F (21 °C). Summer nights throughout the state are characterized by a rapid cooldown with even the hottest locations averaging in the 50–60 °F (10–16 °C) range at night. In most of the state, most of the precipitation tends to fall in the late spring and early summer. Winters are cold, but are variable with periods of sometimes extreme cold interspersed between generally mild periods, with Chinook winds providing unusually warm temperatures in some locations. Wyoming is a dry state with much of the land receiving less than 10 inches (250 mm) of rainfall per year. Precipitation depends on elevation with lower areas in the Big Horn Basin averaging 5–8 inches (130–200 mm) (making the area nearly a true desert). The lower areas in the North and on the eastern plains typically average around 10–12 inches (250–300 mm), making the climate there semi-arid. Some mountain areas do receive a good amount of precipitation, 20 inches (510 mm) or more, much of it as snow, sometimes 200 inches (510 cm) or more annually. The state’s highest recorded temperature is 114 °F (46 °C) at Basin on July 12, 1900 and the lowest recorded temperature is −66 °F (−54 °C) at Riverside on February 9, 1933.

The number of thunderstorm days vary across the state with the southeastern plains of the state having the most days of thunderstorm activity. Thunderstorm activity in the state is highest during the late spring and early summer. The southeastern corner of the state is the most vulnerable part of the state to tornado activity. Moving away from that point and westwards, the incidence of tornadoes drops dramatically with the west part of the state showing little vulnerability. Tornadoes, where they occur, tend to be small and brief, unlike some of those that occur a little farther east.

Transportation

The largest airport in Wyoming is Jackson Hole Airport, with over 500 employees. Three interstate highways and thirteen U.S. highways pass through Wyoming. In addition, the state is served by the Wyoming state highway system.

Interstate 25 enters the state south of Cheyenne and runs north, intersecting Interstate 80 in Cheyenne. It passes through Casper and ends at Interstate 90 near Buffalo. Interstate 80 crosses the Utah border west of Evanston and runs east through the southern half of the state, passing through Cheyenne before entering Nebraska near Pine Bluffs. Interstate 90 comes into Wyoming near Parkman and cuts through the northern part of the state. It serves Gillette and enters South Dakota east of Sundance.

U.S. Routes 14,16, and the eastern section of U.S. 20 all have their western terminus at the eastern entrance to Yellowstone National Park and pass through Cody. U.S. 14 travels eastward before joining I-90 at Gillette. U.S. 14 then follows I-90 to the South Dakota border. U.S. 16 and 20 split off of U.S. 14 at Greybull and U.S. 16 turns east at Worland while U.S. 20 continues south Shoshoni. U.S. Route 287 carries traffic from Fort Collins, Colorado into Laramie, Wyoming through a pass between the Laramie Mountains and the Medicine Bow Mountains, merges with US 30 and I-80 until it reaches Rawlins, where it continues north, passing Lander. Outside of Moran, U.S. 287 is part of a large interchange with U.S. Highways 26, 191, and 89, before continuing north to the southern entrance of Yellowstone. U.S. 287 continues north of Yellowstone, but the two sections are separated by the national park.

Other U.S. highways that pass through the state are U.S. Highways are 18, 26, 30, 85, 87, 89, 189, 191, 212, and 287.

Counties

Wyoming license plates contain a number on the left that indicates the county where the vehicle is registered, ranked by an earlier census. Specifically, the numbers are representative of the property values of the counties in 1930. The county license plate numbers are as follows:

Cities and Towns

The State of Wyoming has 99 incorporated municipalities.

In 2005, 50.6% of Wyomingites lived in one of the 13 most populous Wyoming municipalities.

Metropolitan Areas

The United States Census Bureau has defined two Metropolitan Statistical Areas (MSA) and seven Micropolitan Statistical Areas (MiSA) for the State of Wyoming. In 2008, 30.4% of Wyomingites lived in either of the Metropolitan Statistical Areas, and 73% lived in either a Metropolitan Statistical Area or a Micropolitan Statistical Area.

The Bear River flowing through the southwest part of the state.

Wyoming is one of only two states (the other being South Dakota) in the 48 contiguous states not served by Amtrak.