Intermountain West Climate
Mid-continental location, distant from oceanic moisture sources, leads to abundant sunshine, low humidity and large temperature changes daily and seasonally compared to locations nearer the coasts.
High average elevations also contribute to large temperature changes; the thin air at high elevations heats up faster and cools down faster.
Complex mountainous topography leads to abrupt gradients in both temperature (cooler) and precipitation (wetter) with increasing elevation, drier rain-shadows downwind of mountain ranges, and cold-air pooling in deep valleys and basins.
As a result, the region has enormous spatial variability in climate, with annual precipitation ranging from about 6" to 80" (see figure at right) and mean annual temperatures ranging from around 20°F in the high mountains to 60°F in southern Utah.
The seasonal distribution of precipitation also varies greatly around the region, with the mountains generally seeing a winter peak. Except at the lowest elevations, most or all of the cool-season (October to March) precipitation falls as snow, which has important implications for the region's water cycle.