The geography of the U.S. State of Colorado is diverse, encompassing both rugged mountainous terrain, vast plains, desert lands, desert canyons, and mesas. Colorado is a landlocked U.S. state. In 1861, the United States Congress defined the boundaries of the new Territory of Colorado exclusively by lines of latitude and longitude, stretching from 37°N to 41°N latitude, and from 102°02'48"W to 109°02'48"W longitude (25°W to 32°W from the Washington Meridian). [1] Starting in 1868, official surveys demarcated the boundaries, deviating from the parallels and meridians in several places. Later surveys attempted to correct some of these mistakes but in 1925 the U.S. Supreme Court affirmed that the earlier demarcation was the official boundary. [2] The borders of Colorado are now officially defined by 697 boundary markers connected by straight boundary lines. [3] Colorado, Wyoming, and Utah are the only states that have their borders defined solely by straight boundary lines with no natural features. [4] The southwest corner of Colorado is the Four Corners Monument at 36°59'56"N, 109°2'43"W. [5] [6] This is the only place in the United States where four states meet: Colorado, New Mexico, Arizona, and Utah. [4]
The summit of Mount Elbert at 14,440 feet (4,401.2 m) elevation in Lake County is the state's highest point and the highest point in the Rocky Mountains of North America. [7] Colorado has approximately 550 mountain peaks that exceed 10,000 feet (4,000 metres) elevation. Colorado is the only U.S. state that lies entirely above 3,000 feet (1,000 metres) elevation. The state's lowest elevation is 3,317 feet (1,011 m) at the point on the eastern boundary of Yuma County where the Arikaree River flows into the state of Kansas. [8]
As is common in mountainous and adjacent areas, microclimates exist and weather is strongly influenced by orography. A notable regional atmospheric phenomenon is the Denver Convergence Vorticity Zone (DCVZ) and related Denver Cyclone occurring on the High Plains just east of Denver. The Rocky Mountains as a whole induce significant changes in weather afar, such as the Colorado low.
To the east of the Rocky Mountains in Colorado are the Colorado Eastern Plains/High Plains, the section of the Great Plains within Colorado at elevations ranging from 3,500 to 7,000 feet (1,100 to 2,100 metres). The Midwest states of Kansas and Nebraska border Colorado to the east and northeast.
The plains are sparsely settled with most population along the South Platte and the Arkansas rivers. Rainfall is meager, averaging about 15 inches (380 mm) annually. There is some irrigated farming, but much of the land is used for dryland farming or ranching. Winter wheat is a typical crop and most small towns in the region boast both a water tower and a grain elevator.
The bulk of Colorado's population lives along the eastern edge of the Rocky Mountains in the Front Range Urban Corridor. This region is partially protected from prevailing storms by the high mountains to the west.
To the west lies the eastern slope of the Rocky Mountains with notable peaks such as Longs Peak, Mount Blue Sky, Pikes Peak, and the Spanish Peaks near Walsenburg in the south. This area drains to the east, is forested, and partially urbanized. With urbanization, utilization of the forest for timbering and grazing resulted in accumulation of fuel. During the drought of 2002 devastating forest fires swept this area.
The Continental Divide stretches along the crest of the Rocky Mountains. To the west of the Continental Divide is the Western Slope. Water west of the Continental Divide drains west into the Pacific Ocean via the Colorado River. Western Colorado is made up of mountains, mesas, desert canyons, and desert lands.
Within the interior of the Rocky Mountains are several large parks or high broad basins. In the north, on the east side of the Continental Divide is North Park. North Park is drained by the North Platte River, which flows north into the northwest state of Wyoming. Just south but on the west side of the Continental Divide is Middle Park, drained by the Colorado River. South Park is the headwaters of the South Platte River. To the south lies the San Luis Valley, the headwaters of the Rio Grande, which drains into New Mexico. Across the Sangre de Cristo Range to the east of the San Luis Valley lies the Wet Mountain Valley. These basins, particularly the San Luis Valley, lie along the Rio Grande Rift, a major tectonic feature. See Rift.
The Rocky Mountains within Colorado contain 54 peaks that are 14,000 ft (4,300 m) or higher, known as fourteeners. [9] The mountains are timbered with conifers and aspen to the tree line, at an elevation of about 12,000 ft (3,700 m) in southern Colorado to about 10,500 ft (3,200 m) in northern Colorado; above this only alpine vegetation grows. The Rockies are snow-covered only in the winter; most snow melts by mid-August with the exception of a few small glaciers. The Colorado Mineral Belt, stretching from the San Juan Mountains in the southwest to Boulder and Central City on the front range, contains most of the historic gold and silver mining districts of Colorado.
The Western Slope is generally drained by the Colorado River and its tributaries. Notable to the south are the San Juan Mountains, an extremely rugged mountain range, and to the west of the San Juans, the Colorado Plateau, a high desert extending into neighboring states. Grand Junction is the largest city on the Western Slope. Grand Junction is served by Interstate Highway 70. To the southeast of Grand Junction is Grand Mesa, a large flat-topped desert mountain. Further east are the ski resort communities of Aspen, Vail, Crested Butte, and Steamboat Springs. The northwestern corner of Colorado bordering Northern Utah and Western Wyoming is mostly sparsely populated rangeland.
From west to east, the state consists of desert basins, desert canyons and mesas, turning into desert plateaus, then alpine mountains, and then the grasslands of the High Plains. Mount Elbert is the highest peak in the Rocky Mountains of North America. The famous Pikes Peak is just west of Colorado Springs. Its lone peak is visible from near the Kansas border on clear days.
Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Record high °F (°C) | 76 (24) | 80 (27) | 84 (29) | 90 (32) | 95 (35) | 105 (41) | 105 (41) | 105 (41) | 101 (38) | 90 (32) | 81 (27) | 79 (26) | 105 (41) |
Mean maximum °F (°C) | 65.0 (18.3) | 67.1 (19.5) | 74.7 (23.7) | 80.8 (27.1) | 88.3 (31.3) | 96.5 (35.8) | 99.6 (37.6) | 96.9 (36.1) | 92.9 (33.8) | 84.1 (28.9) | 73.6 (23.1) | 65.3 (18.5) | 100.6 (38.1) |
Mean daily maximum °F (°C) | 44.6 (7.0) | 45.7 (7.6) | 55.7 (13.2) | 61.7 (16.5) | 71.2 (21.8) | 83.4 (28.6) | 89.9 (32.2) | 87.5 (30.8) | 79.6 (26.4) | 65.3 (18.5) | 52.9 (11.6) | 44.0 (6.7) | 65.1 (18.4) |
Daily mean °F (°C) | 31.7 (−0.2) | 32.7 (0.4) | 41.6 (5.3) | 47.8 (8.8) | 57.4 (14.1) | 68.2 (20.1) | 75.1 (23.9) | 72.9 (22.7) | 64.8 (18.2) | 51.1 (10.6) | 39.4 (4.1) | 31.2 (−0.4) | 51.2 (10.6) |
Mean daily minimum °F (°C) | 18.7 (−7.4) | 19.7 (−6.8) | 27.5 (−2.5) | 33.9 (1.1) | 43.6 (6.4) | 53.0 (11.7) | 60.2 (15.7) | 58.3 (14.6) | 50.0 (10.0) | 37.0 (2.8) | 26.0 (−3.3) | 18.4 (−7.6) | 37.2 (2.9) |
Mean minimum °F (°C) | −3.8 (−19.9) | −1.5 (−18.6) | 9.5 (−12.5) | 19.8 (−6.8) | 30.2 (−1.0) | 41.9 (5.5) | 51.4 (10.8) | 48.8 (9.3) | 35.9 (2.2) | 19.6 (−6.9) | 5.4 (−14.8) | −3.4 (−19.7) | −11 (−24) |
Record low °F (°C) | −29 (−34) | −25 (−32) | −11 (−24) | −2 (−19) | 19 (−7) | 30 (−1) | 42 (6) | 40 (4) | 17 (−8) | −2 (−19) | −18 (−28) | −25 (−32) | −29 (−34) |
Average precipitation inches (mm) | 0.38 (9.7) | 0.41 (10) | 0.86 (22) | 1.68 (43) | 2.16 (55) | 1.94 (49) | 2.14 (54) | 1.58 (40) | 1.35 (34) | 0.99 (25) | 0.64 (16) | 0.35 (8.9) | 14.48 (368) |
Average snowfall inches (cm) | 6.4 (16) | 7.6 (19) | 8.8 (22) | 6.2 (16) | 1.4 (3.6) | 0.0 (0.0) | 0.0 (0.0) | 0.0 (0.0) | 0.8 (2.0) | 3.9 (9.9) | 7.3 (19) | 6.6 (17) | 49.0 (124) |
Average precipitation days (≥ 0.01 in) | 4.4 | 5.5 | 6.2 | 9.0 | 10.4 | 8.1 | 8.3 | 7.5 | 6.0 | 5.3 | 4.6 | 4.4 | 79.7 |
Average snowy days (≥ 0.1 in) | 5.0 | 5.3 | 4.8 | 4.1 | 0.8 | 0.0 | 0.0 | 0.0 | 0.4 | 1.8 | 4.6 | 4.6 | 31.4 |
Average relative humidity (%) | 55.2 | 55.8 | 53.7 | 49.6 | 51.7 | 49.3 | 47.8 | 49.3 | 50.1 | 49.2 | 56.3 | 56.6 | 52.0 |
Average dew point °F (°C) | 12.7 (−10.7) | 16.2 (−8.8) | 19.9 (−6.7) | 26.2 (−3.2) | 35.8 (2.1) | 43.5 (6.4) | 48.4 (9.1) | 47.7 (8.7) | 39.6 (4.2) | 28.6 (−1.9) | 21.0 (−6.1) | 14.2 (−9.9) | 29.5 (−1.4) |
Mean monthly sunshine hours | 215.3 | 211.1 | 255.6 | 276.2 | 290.0 | 315.3 | 325.0 | 306.4 | 272.3 | 249.2 | 194.3 | 195.9 | 3,106.6 |
Mean daily daylight hours | 9.7 | 10.7 | 12 | 13.3 | 14.4 | 15 | 14.7 | 13.7 | 12.4 | 11.1 | 10 | 9.4 | 12.2 |
Percent possible sunshine | 72 | 70 | 69 | 69 | 65 | 70 | 71 | 72 | 73 | 72 | 65 | 67 | 70 |
Average ultraviolet index | 2 | 2 | 3 | 3 | 5 | 6 | 6 | 5 | 5 | 3 | 2 | 2 | 4 |
Source 1: NOAA (sun, relative humidity and dew point 1961−1990) [10] [11] [12] [13] [14] | |||||||||||||
Source 2: Weather Atlas (Daylight-Average UV index) [15] |
Climate data for Grand Junction, Colorado (Grand Junction Regional Airport), 1991–2020 normals, [lower-alpha 3] extremes 1893–present [lower-alpha 4] | |||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Month | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | Year |
Record high °F (°C) | 62 (17) | 70 (21) | 81 (27) | 89 (32) | 101 (38) | 105 (41) | 107 (42) | 103 (39) | 100 (38) | 88 (31) | 76 (24) | 66 (19) | 107 (42) |
Mean maximum °F (°C) | 49.6 (9.8) | 60.0 (15.6) | 72.6 (22.6) | 81.3 (27.4) | 90.9 (32.7) | 99.4 (37.4) | 102.0 (38.9) | 98.6 (37.0) | 93.2 (34.0) | 82.1 (27.8) | 65.3 (18.5) | 51.9 (11.1) | 102.5 (39.2) |
Mean daily maximum °F (°C) | 38.1 (3.4) | 46.4 (8.0) | 58.3 (14.6) | 65.8 (18.8) | 76.8 (24.9) | 89.2 (31.8) | 94.5 (34.7) | 90.9 (32.7) | 81.7 (27.6) | 66.9 (19.4) | 51.8 (11.0) | 38.8 (3.8) | 66.6 (19.2) |
Daily mean °F (°C) | 27.7 (−2.4) | 35.3 (1.8) | 45.0 (7.2) | 51.9 (11.1) | 62.0 (16.7) | 73.0 (22.8) | 79.2 (26.2) | 76.3 (24.6) | 67.1 (19.5) | 53.2 (11.8) | 39.6 (4.2) | 28.4 (−2.0) | 53.2 (11.8) |
Mean daily minimum °F (°C) | 17.3 (−8.2) | 24.1 (−4.4) | 31.7 (−0.2) | 38.1 (3.4) | 47.1 (8.4) | 56.8 (13.8) | 63.9 (17.7) | 61.6 (16.4) | 52.5 (11.4) | 39.5 (4.2) | 27.5 (−2.5) | 18.0 (−7.8) | 39.8 (4.3) |
Mean minimum °F (°C) | 3.4 (−15.9) | 10.3 (−12.1) | 19.3 (−7.1) | 25.4 (−3.7) | 33.6 (0.9) | 44.3 (6.8) | 54.3 (12.4) | 53.5 (11.9) | 39.2 (4.0) | 25.4 (−3.7) | 13.8 (−10.1) | 2.8 (−16.2) | −1.3 (−18.5) |
Record low °F (°C) | −23 (−31) | −21 (−29) | 5 (−15) | 11 (−12) | 24 (−4) | 34 (1) | 44 (7) | 43 (6) | 28 (−2) | 6 (−14) | −4 (−20) | −21 (−29) | −23 (−31) |
Average precipitation inches (mm) | 0.61 (15) | 0.53 (13) | 0.80 (20) | 0.98 (25) | 0.83 (21) | 0.41 (10) | 0.59 (15) | 0.92 (23) | 1.19 (30) | 0.99 (25) | 0.61 (15) | 0.60 (15) | 9.06 (230) |
Average snowfall inches (cm) | 4.5 (11) | 2.9 (7.4) | 1.8 (4.6) | 0.9 (2.3) | 0.1 (0.25) | 0.0 (0.0) | 0.0 (0.0) | 0.0 (0.0) | 0.0 (0.0) | 0.4 (1.0) | 1.9 (4.8) | 5.2 (13) | 17.7 (44.35) |
Average precipitation days (≥ 0.01 in) | 6.3 | 6.1 | 6.7 | 7.1 | 6.4 | 3.4 | 4.8 | 6.5 | 6.5 | 6.2 | 5.4 | 6.1 | 71.6 |
Average snowy days (≥ 0.1 in) | 4.6 | 3.5 | 1.7 | 0.7 | 0.1 | 0.0 | 0.0 | 0.0 | 0.0 | 0.5 | 2.0 | 5.0 | 18.1 |
Average relative humidity (%) | 69.7 | 60.4 | 50.1 | 40.3 | 36.3 | 29.4 | 33.5 | 36.6 | 38.8 | 45.6 | 58.5 | 68.0 | 47.3 |
Mean monthly sunshine hours | 192.3 | 204.4 | 240.9 | 278.0 | 328.5 | 359.3 | 356.2 | 329.8 | 292.2 | 255.1 | 186.9 | 180.0 | 3,203.6 |
Percent possible sunshine | 63 | 68 | 65 | 70 | 74 | 81 | 79 | 78 | 78 | 74 | 62 | 61 | 72 |
Source: NOAA (sun 1961–1990) [16] [17] |
Colorado is a landlocked state in the Mountain West subregion of the Western United States. Colorado borders Wyoming to the north, Nebraska to the northeast, Kansas to the east, Oklahoma to the southeast, New Mexico to the south, Utah to the west, and meets Arizona to the southwest at the Four Corners. Colorado is noted for its landscape of mountains, forests, high plains, mesas, canyons, plateaus, rivers, and desert lands. Colorado is one of the Mountain States and is often considered to be part of the southwestern United States. The high plains of Colorado may be considered a part of the midwestern United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains. Colorado is the eighth most extensive and 21st most populous U.S. state. The United States Census Bureau estimated the population of Colorado at 5,877,610 as of July 1, 2023, a 1.80% increase since the 2020 United States census.
The term "United States," when used in the geographical sense, refers to the contiguous United States, Alaska, Hawaii, the five insular territories of Puerto Rico, Northern Mariana Islands, U.S. Virgin Islands, Guam, American Samoa, and minor outlying possessions. The United States shares land borders with Canada and Mexico and maritime borders with Russia, Cuba, The Bahamas, and many other countries, mainly in the Caribbeanin addition to Canada and Mexico. The northern border of the United States with Canada is the world's longest bi-national land border.
The South Platte River is one of the two principal tributaries of the Platte River. Flowing through the U.S. states of Colorado and Nebraska, it is itself a major river of the American Midwest and the American Southwest/Mountain West. Its drainage basin includes much of the eastern flank of the Rocky Mountains in Colorado, much of the populated region known as the Colorado Front Range and Eastern Plains, and a portion of southeastern Wyoming in the vicinity of the city of Cheyenne. It joins the North Platte River in western Nebraska to form the Platte, which then flows across Nebraska to the Missouri. The river serves as the principal source of water for eastern Colorado. In its valley along the foothills in Colorado, it has permitted agriculture in an area of the Colorado Piedmont and Great Plains that is otherwise arid.
The Platte River is a major river in the State of Nebraska. It is about 310 mi (500 km) long; measured to its farthest source via its tributary, the North Platte River, it flows for over 1,050 miles (1,690 km). The Platte River is a tributary of the Missouri River, which itself is a tributary of the Mississippi River which flows to the Gulf of Mexico. The Platte over most of its length is a broad, shallow, meandering stream with a sandy bottom and many islands—a braided stream.
The North Platte River is a major tributary of the Platte River and is approximately 716 miles (1,152 km) long, counting its many curves. In a straight line, it travels about 550 miles (890 km), along its course through the U.S. states of Colorado, Wyoming, and Nebraska.
Grays Peak is the tenth-highest summit of the Rocky Mountains of North America and the U.S. state of Colorado. The prominent 14,278-foot (4352 m) fourteener is the highest summit of the Front Range and the highest point on the Continental Divide and the Continental Divide Trail in North America. Grays Peak is located in Arapahoe National Forest, 3.9 miles (6.2 km) southeast by east of Loveland Pass on the Continental Divide between Clear Creek and Summit counties. The peak is the highest point in both counties.
The Medicine Bow Mountains are a mountain range in the Rocky Mountains that extend 100 miles (160 km) from northern Colorado into southern Wyoming. The northern extent of this range is the sub-range the Snowy Range. From the northern end of Colorado's Never Summer Mountains, the Medicine Bow mountains extend north from Cameron Pass along the border between Larimer and Jackson counties in Colorado and northward into south central Wyoming. In Wyoming, the range sits west of Laramie, in Albany and Carbon counties to the route of the Union Pacific Railroad and U.S. Interstate 80. The mountains often serve as a symbol for the city of Laramie. The range is home to Snowy Range Ski Area.
Cameron Pass is a mountain pass in north-central Colorado in the Rocky Mountains of the western United States. The pass is a gap between the south end of the Medicine Bow Mountains and the north end of the Never Summer Mountains. It sits on the border between Jackson County and Larimer County, approximately 3 mi north of the boundary of Rocky Mountain National Park. The pass provides the most convenient route between Fort Collins and Walden in North Park, using State Highway 14.
Named after Colorado Springs founder William Jackson Palmer, the Palmer Divide is a caprock escarpment-style ridge in central Colorado that separates the Arkansas River basin from the South Platte basin. It extends from the Front Range of the Rockies in central Colorado eastward approximately 80 miles toward the town of Limon. The western end of the Palmer Divide is popularly considered to be at Palmer Lake, located south of Denver and north of Colorado Springs. However, the divide between the two river basins actually extends west and then north to a junction with the Continental Divide at McNamee Peak.
The landlocked U.S. state of Nevada has a varied geography and is almost entirely within the Basin and Range Province and is broken up by many north–south mountain ranges. Most of these ranges have endorheic valleys between them.
The U.S. state of Idaho borders six other U.S. states and one Canadian province. The states of Washington and Oregon are to the west, Nevada and Utah are to the south, and Montana and Wyoming are to the east. Idaho also shares a short border with the Canadian province of British Columbia to the north.
Arizona is a landlocked state situated in the southwestern region of the United States of America. It has a vast and diverse geography famous for its deep canyons, high- and low-elevation deserts, numerous natural rock formations, and volcanic mountain ranges. Arizona shares land borders with Utah to the north, the Mexican state of Sonora to the south, New Mexico to the east, and Nevada to the northwest, as well as water borders with California and the Mexican state of Baja California to the southwest along the Colorado River. Arizona is also one of the Four Corners states and is diagonally adjacent to Colorado.
The U.S. state of Wyoming lies in the Mountain West subregion of the Western United States and has a varied geography. It is bordered by Montana to the north and northwest, South Dakota and Nebraska to the east, Idaho to the west, Utah to the southwest, and Colorado to the south. Wyoming is the least populous U.S. state and has the second-lowest population density behind Alaska.
The following outline is provided as an overview of and topical guide to the U.S. state of Colorado:
The Mountain states form one of the nine geographic divisions of the United States that are officially recognized by the United States Census Bureau. It is a subregion of the Western United States.