Oklahoma Geography

Oklahoma is one of the six states on the Frontier Strip. It is bounded on the east by Arkansas and Missouri, on the north by Kansas and northwest by Colorado (both at 37°N), on the far west by New Mexico (at 103°W), and on the south and near-west by Texas. The panhandle's southern boundary is at 36.5°N, then turning due south along 100°W to the southern fork of the Red River), completing the round trip back to Arkansas.

Oklahoma has three primary mountain ranges: Ouachitas, Arbuckles, and the Kiamichis. In addition to several smaller ranges, Oklahoma also notably encompasses a portion of the Ozarks. Along with the Black Hills of South Dakota, the Ozarks and the Ouachita Mountains are the only major highland regions between the Rocky Mountains and the Appalachians. The state's highest peak, Black Mesa (4,973 feet (1,516 m)), lies in the far northwestern corner of the panhandle near the town of Kenton. The lowest elevation is in the far southeastern of the state, is at the Little River , at 289 feet (88 m). Oklahoma also has what is officially considered the highest hill in the world, Cavanal Hill, at 1,999 feet (609 m); this is considering the fact that a "mountain" is anything 2,000 feet or higher. It is located in Poteau, Oklahoma.[8]

Oklahoma has six tripoints. In the Gulf of Mexico Watershed, most of Oklahoma's topography is a plain sloping towards the east. Most water leaves the state through the Red, Washita, Canadian, Cimarron and Arkansas Rivers. Some of the major rivers are the Canadian River and the Cimarron River. With 200 man-made lakes, the state has more man-made lakes than any other state and boasts over one million surface-acres of water and 2,000 more miles (3,200 km) of shoreline than the Atlantic and Gulf coasts combined. Lake Eufaula is the largest lake in the state, covering 102,000 acres (413 km²) of water.[8]

According to the EPA, Oklahoma has the most diverse terrain in the United States. [9] The EPA recognizes Oklahoma as one of only four U.S. states to have more than 10 distinct ecological regions, with 11 within its borders. The high number of ecoregions coupled with the state's relative size and a drastic change in climate progressively from the northwest to southeast makes each Oklahoma region greatly distinctive from the next.

Located primarily in the northwest part of the state, the Southwest Tablelands Ecoregion is far more indicative of the American-Southwest than the rest of Oklahoma, containing mesa ranges such as Black Mesa and the Glass Mountains, as well as canyons and grasslands, such as the Rita Blanca National Grassland. The Northwestern section of Oklahoma, including most of the panhandle, also contains nearly all of the state's "true plains," terrain indicative of the Great Plains ecoregion, which contains few natural forests and rolling to flat semi-arid landscape. Partial plains interrupted by small mountain ranges such as the Antelope Hills and the rocky Wichita Mountains near Lawton make up the state's southwest quarter, while Central Oklahoma transitions to rolling more forested terrain and marks the eastern extent of the Great Plains in Oklahoma. Most of the region is dominated by the Cross Timbers ecoregion, which is a combination of prairie and forest which transitions to the wetter eastern third of the state. A portion of the prairie-covered Flint Hills stretching from Kansas, creeps into north-central Oklahoma and holds the largest protected area of tallgrass prairie in the world at the Tallgrass Prairie Preserve near Pawhuska. Eastern Oklahoma receives far more rain than the western parts of the state and contains a large number of Oklahoma's 200 man-made lakes, including large-scale water destinations such as Lake Eufaula and Grand Lake O' the Cherokees. Most of the Ouachita Mountains in Oklahoma are located in the southeast quarter of the state and hold the popular Talimena National Scenic Drive, which travels through the Ouachita National Forest. The heavily-wooded Ozark Mountains and their foothills dominate most of northeastern Oklahoma from the immediate Tulsa vicinity south and eastward towards the Arkansas border, containing heavy forests of pine and deciduous trees.

The Oklahoma Tourism Department divides the state down into six regions for tourism promotion purposes: Red Carpet Country (Northwestern Oklahoma and The Panhandle), Great Plains Country (Southwestern Oklahoma, including the Lawton Metropolitan area), Frontier Country (Central Oklahoma, including the Oklahoma City Metropolitan area), Green Country (Northeastern Oklahoma, including the Tulsa Metropolitan area), Kiamichi country (Southeastern Oklahoma), and Lake & Trail Country (South Central Oklahoma).

Popular but "unofficial" regional designations include "Green Country" (deemed "unofficial" when used outside of its official Tourism definition, such as referring to all of Eastern Oklahoma or the Tulsa Metropolitan Area), Little Dixie (Southeastern Oklahoma), Western Oklahoma, and the Oklahoma Panhandle.

Oklahoma is a state dominated by contrasting cold and warm air masses that collide east of the Rocky Mountains. As can be expected, this results in a wide range of weather throughout the state, ranging from a borderline humid subtropical climate zone near the southeast part of the state to a semi-arid climate in the High Plains of the panhandle. While there is some variation in temperature in the state, with the south portion on the Texas border averaging an annual mean temperature of 62 °F (17 °C), and the panhandle averaging under 54 °F (12 °C), the main climatic difference in Oklahoma is precipitation.[citation needed] The southeast corner of the state near the Ouachita Mountains averages over 52 inches (1,321 mm) of precipitation a year.[citation needed] Moving west from that point, the precipitation decreases rapidly- for each 10 miles (16 km) traveled west, the precipitation is approximately 1 inch (25 mm) less.[citation needed] The driest part of the state is the extreme western panhandle with less than 16 inches (406 mm) annually.[citation needed] Snowfall, although not extreme, is common in the state, ranging from an average of less than 4 inches (102 mm) inches in the southern part of the state to just over 20 inches on the Colorado border in the panhandle.[citation needed]

The most notable feature of Oklahoma's climate is its thunderstorms. While Oklahoma averages from 40-60 days of thunderstorms throughout the entire state,[citation needed] this is less frequent than thunderstorm activity in parts of the Southeast United States and the central Colorado Rockies.[citation needed] However, occurring in a "fifth season" from April through July, Oklahoma thunderstorms tend to be among the most severe in the world.[citation needed] During this period, cold airmasses from the north and warm airmasses from the south colide, making the state vulnerable to severe weather outbreaks. Most of Oklahoma lies in the heart of Tornado Alley, and central Oklahoma is the most tornado-prone area in the world, not only in terms of number of tornadoes, exceeding 10 per 10,000 square miles, but in terms of intensity of tornadoes.[10] The highest wind speed ever recorded on Earth was measured during the 3 May 1999 tornado outbreak.[citation needed] 318 mile per hour (512 km/h) winds hit areas near Oklahoma City during this outbreak.[citation needed] Its unique weather patterns make the state a hospitable location for the National Severe Storms Laboratory and the National Weather Service's Storm Prediction Center, located in Norman.

Map of Oklahoma

Bunch and Beaver Mountains in the Cookson Hills of eastern Oklahoma.

View from Talimena National Drive in the Ouachita National Forest

A canyon in the Wichita Mountains.

The Glass Mountains, a range of mesas in Northwest Oklahoma.

Lightning over downtown Tulsa. Lightning is a common sight in Oklahoma during the spring months.

A wind farm in Western Oklahoma.