Idaho local data guide

Average Temperatures in Boise, Idaho

Boise experiences a semi-arid climate characterized by four distinct seasons, featuring hot, dry summers and cold, snowy winters. Based on the 1991–2020 climatological normals from the National Weather Service, Boise's temperatures reflect its high-desert geography in the Treasure Valley. These figures represent long-term climate averages and do not indicate current daily weather conditions.

Updated with grounded research as of 2026-07-20.

The short answer

Boise, Idaho, has an average annual temperature of approximately 53.2°F, based on data collected at the Boise Air Terminal during the 1991–2020 normal period. While the city experiences four distinct seasons, its semi-arid climate means the region typically features hot, dry summers where temperatures frequently reach the 90s°F and cold, partially cloudy winters with temperatures often hovering between 25°F and 40°F.

Key facts

Average Annual Temperature: 53.2°F (1991–2020 Normal)
Official Climate Data Authority: National Weather Service (NWS) Boise

Understanding Seasonal Variations

Boise’s weather is shaped by the surrounding mountains and its position in the Treasure Valley. Summers are short and hot, often seeing multiple days exceeding 100°F during the peak of July and August. Winters are characterized by cold temperatures and moderate snowfall, usually lasting from late November through mid-March.

Geographic Influences

Boise sits at an elevation of approximately 2,700 feet. The region's semi-arid nature results in relatively low annual precipitation, averaging about 12 inches. Because the area is inland and shielded by mountain ranges, it rarely experiences extreme weather events like hurricanes or blizzards, contributing to a moderate climate compared to other northern cities at similar latitudes.

Planning and Real Estate Considerations

For those relocating to the area, it is important to note that microclimates exist within the Treasure Valley; temperatures can vary slightly between the Boise Airport, the downtown foothills, and more rural parts of the valley. Homeowners should plan for seasonal heating and cooling needs and be aware of fire-wise landscaping requirements due to the dry summer conditions.

Common questions

What is the typical temperature range in summer and winter?

In summer (July), average highs typically peak near 92°F. In winter (January), average lows often dip to 25°F with highs hovering near 38°F.

Does Boise have extreme weather?

Extreme weather like tornadoes, hurricanes, or severe blizzards is extremely rare in Boise. The city is known for relatively mild, 'boring' weather that supports year-round outdoor activities.

Sources and verification

Review National Weather Service climate data (weather.gov)