Lemhi County Climate
Lemhi County, Idaho
Avg Annual Temp
43.2°F
Annual Precip
9.0"
Annual Snowfall
22.0"
Extreme Heat Days
24.339999999999996
days >= 90°F/yr
Monthly Temperature
Precipitation Calendar
Seasonal Overview
National Comparison
Climate Profile
About Lemhi County Weather
A cold and arid mountain retreat
Lemhi County is one of the colder spots in the country, with an annual average temperature of just 43.2°F. It is extremely dry, receiving only 9.0 inches of annual precipitation.
Much colder than the state average
The county's 43.2°F average is over three degrees colder than the Idaho state average of 46.5°F. It is also one of the driest counties in the state, falling 8 inches below the state's 17-inch precipitation average.
Colder than Jefferson and Idaho counties
Lemhi County is notably colder than Jefferson and Idaho counties, which both average 44.8°F. It also receives the least precipitation among its regional peers, totaling only 9 inches annually.
Harsh winters and sharp summer spikes
January is frigid with an average of 20.0°F and 22 inches of annual snowfall. Despite the cold year-round average, the county still experiences 24 days above 90°F during the dry summer months.
Prepare for the deep freeze
Heavy-duty home insulation and reliable heating sources are critical to surviving the 20°F January average. Residents should also plan for dry conditions by utilizing moisture-retaining landscaping to manage the low rainfall.
Frequently Asked Questions
What is the average temperature in Lemhi County?
How much rain does Lemhi County get?
Does it snow in Lemhi County?
How hot does Lemhi County get in summer?
How cold are winters in Lemhi County?
Track your own weather in Lemhi County
Ambient Weather personal weather stations give you hyperlocal climate data.
Sponsored
Data source: NOAA National Centers for Environmental Information (NCEI), U.S. Climate Normals 1991-2020.
Climate normals are 30-year averages of weather variables computed from 1991 to 2020. Station data is aggregated to county level using spatial averaging. Data is informational only — not a substitute for official National Weather Service forecasts or emergency weather warnings.