Intermountain West

The Intermountain West, or Intermountain Region, is a geographic and geological region of the Western United States. It is located between the front ranges of the Rocky Mountains on the east and the Cascade Range and Sierra Nevada on the west.

The Intermountain West has a basin and range and plateau topography. Some of the region's rivers reach the Pacific Ocean, such as the Columbia River and Colorado River. Other regional rivers and streams are in endorheic basins and cannot reach the sea, such as the Walker River and Owens River. These flow into brackish or seasonally dry lakes or desert sinks.
Portions of this region include:

The climate of the Intermountain Region is affected by location and elevation. The sub-regions are in rain shadows from the Cascade or Sierra Nevada ranges that block precipitation from Pacific storms. The winter weather depends on latitude. In the southern portion, winters are shorter, warmer and have less winter precipitation and snow. In the northern portion, winters are cold and moist. All areas have hot summers. North American Monsoon storms can occur in the region during the mid-summer, coming northeast from the Pacific Ocean and Mexican Plateau.

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