High Plains (United States)




 * This article is about a geographic region in the United States. For the High Plains of Victoria and New South Wales, Australia, see High Plains (Australia).

The High Plains are a subregion of the Great Plains in the central United States, generally encompassing the western part of the Great Plains before the region reaches the Rocky Mountains. The High Plains are located in eastern Colorado, western Kansas, western Nebraska, central and eastern Montana, eastern New Mexico, western Oklahoma, northwestern Texas, and southeastern Wyoming. In some definitions of the subregion, parts of western South Dakota and North Dakota are included. From east to west, the High Plains rise in elevation from around 750 m (2500 ft) to over 1800 m (6000 ft).

The High Plains are semiarid, receiving between 250–500 mm (10–20 in) of precipitation annually. Shortgrass prairie, prickly pear cacti and scrub vegetation cover the region, with occasional buttes or other rocky outcrops. Agriculture in the forms of cattle ranching and the growing of wheat, cotton and sunflowers is the primary economic activity in the region. The aridity of the region necessitates either dryland farming methods or irrigation; much water for irrigation is drawn from the underlying Ogallala Aquifer. Some areas have significant petroleum and natural gas deposits.

The High Plains has one of the lowest population densities of any region in the continental United States; Wyoming, for example, has the second lowest population density in the country before Alaska. In contrast to the rather low and stagnant population in the northern and western High Plains, cities in west Texas have shown sustained growth; Amarillo and Lubbock both have populations near or above 200,000 and continue to grow. Smaller towns, on the other hand, often struggle to sustain their population.



Due to low moisture and high elevation, the High Plains commonly experiences wide ranges and extremes in temperature. The temperature range from day to night commonly exceeds 59 degrees F (33 degrees Celsius), and 24-hour temperature shifts of 68-77 degrees F (38 to 43 degrees Celsius) are not unknown. The region is known for the steady, and sometimes intense, winds that prevail from the west. The winds add a considerable wind chill factor in the winter. The development of wind farms in the High Plains is one of the newest areas of economic development.

The combination of oil, natural gas, and wind energy along with plentiful underground water, has allowed some areas (such as west Texas) to sustain a range of economic activity, including occasional industry. For example, the Asarco refinery in Amarillo, Texas has been in operation since 1924 due to the plentiful and inexpensive natural gas and water that are needed in metal ore refining.