Idaho experiences a typical four-season climate but spring comes earlier and winter later to Boise and Lewiston, which are protected from severe weather by nearby mountains. Eastern Idaho has a more continental climate, with more extreme temperatures. Mean temperatures in Boise range from 29°F (–2°C) in January to 74°F (23°C) in July.

Humidity is low throughout the state while the average annual precipitation at Boise is 12.2 inches.