Bield:Farm
Frost dates · Idaho

Idaho frost dates,
county by county.

Last spring frost and first fall frost probability data for all 44 counties in Idaho, computed from the NOAA 1991–2020 Climate Normals. Every county page surfaces the full probability table at three temperature thresholds plus crop-specific planting guidance.

Variation across Idaho

64 days separate the earliest and latest counties.

The median last spring frost in Owyhee County is March 30 — 64 days earlier than Blaine County at June 2. Statewide averages aren't useful planting tools; pick your county below for the data that actually applies to your fields.

By geography

Idaho counties on the map.

Each dot is a county. Click for full frost-date detail. Color shows last-spring-frost timing — sage = earliest, amber = latest.

ListMap
Lincoln County · Spring May 8 · Fall Oct 7 · 152-day seasonBenewah County · Spring Apr 14 · Fall Oct 19 · 188-day seasonBoundary County · Spring Apr 10 · Fall Oct 16 · 189-day seasonCuster County · Spring May 1 · Fall Oct 7 · 159-day seasonJefferson County · Spring May 14 · Fall Sep 21 · 130-day seasonValley County · Spring May 16 · Fall Sep 24 · 131-day seasonGem County · Spring May 7 · Fall Sep 29 · 145-day seasonLemhi County · Spring May 2 · Fall Oct 5 · 156-day seasonIdaho County · Spring May 22 · Fall Sep 7 · 108-day seasonCassia County · Spring May 17 · Fall Sep 26 · 132-day seasonBlaine County · Spring Jun 2 · Fall Sep 23 · 113-day seasonGooding County · Spring Apr 19 · Fall Oct 15 · 179-day seasonOneida County · Spring May 4 · Fall Oct 2 · 151-day seasonBoise County · Spring May 15 · Fall Sep 23 · 131-day seasonBonneville County · Spring May 19 · Fall Sep 23 · 127-day seasonShoshone County · Spring Apr 24 · Fall Oct 14 · 173-day seasonJerome County · Spring Apr 23 · Fall Oct 17 · 177-day seasonKootenai County · Spring Apr 1 · Fall Nov 1 · 214-day seasonElmore County · Spring May 30 · Fall Sep 18 · 111-day seasonFremont County · Spring May 3 · Fall Oct 4 · 154-day seasonBonner County · Spring Apr 21 · Fall Oct 10 · 172-day seasonCamas County · Spring May 11 · Fall Sep 28 · 140-day seasonMinidoka County · Spring May 2 · Fall Oct 15 · 166-day seasonBannock County · Spring May 4 · Fall Oct 4 · 153-day seasonTeton County · Spring May 22 · Fall Sep 20 · 121-day seasonPayette County · Spring Mar 31 · Fall Oct 31 · 214-day seasonClark County · Spring May 10 · Fall Oct 2 · 145-day seasonPower County · Spring Apr 19 · Fall Oct 21 · 185-day seasonLewis County · Spring May 5 · Fall Oct 2 · 150-day seasonNez Perce County · Spring May 2 · Fall Oct 9 · 160-day seasonTwin Falls County · Spring Apr 25 · Fall Oct 15 · 173-day seasonButte County · Spring May 6 · Fall Oct 3 · 150-day seasonClearwater County · Spring May 17 · Fall Sep 20 · 126-day seasonAdams County · Spring Apr 22 · Fall Oct 16 · 177-day seasonBear Lake County · Spring May 25 · Fall Sep 16 · 114-day seasonFranklin County · Spring Apr 30 · Fall Oct 10 · 163-day seasonLatah County · Spring Apr 28 · Fall Oct 5 · 160-day seasonOwyhee County · Spring Mar 30 · Fall Oct 31 · 215-day seasonMadison County · Spring Apr 30 · Fall Oct 7 · 160-day seasonBingham County · Spring Apr 22 · Fall Oct 16 · 177-day seasonWashington County · Spring Apr 28 · Fall Oct 7 · 162-day seasonAda County · Spring Apr 2 · Fall Oct 31 · 212-day seasonCanyon County · Spring Apr 5 · Fall Oct 30 · 208-day seasonCaribou County · Spring May 27 · Fall Sep 12 · 108-day season
Last spring frostEarliestMedianLatest
44 counties · click any county for full frost data
Alphabetical

All Idaho counties — A to Z.

Frost dates set the calendar. Bield: Farm runs it.

Pair these dates with live forecasts for your specific farm location. Bield: Farm logs your soil tests, planting dates, weather, and yield outcomes year over year.

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