Idaho frost dates by county and ZIP code
Across 280 Idaho ZIP codes the average last spring frost runs Apr 2 to Jun 20 and the average first fall frost Sep 1 to Nov 5 (50% odds, 32°F, NOAA 1991–2020 normals), with USDA hardiness zones. Download the table as CSV.
Counties
- Ada
- Adams
- Bannock
- Bear Lake
- Benewah
- Bingham
- Blaine
- Boise
- Bonner
- Bonneville
- Boundary
- Butte
- Camas
- Canyon
- Caribou
- Cassia
- Clark
- Clearwater
- Custer
- Elmore
- Franklin
- Fremont
- Gem
- Gooding
- Idaho
- Jefferson
- Jerome
- Kootenai
- Latah
- Lemhi
- Lewis
- Lincoln
- Madison
- Minidoka
- Nez Perce
- Oneida
- Owyhee
- Payette
- Power
- Shoshone
- Teton
- Twin Falls
- Valley
- Washington
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