Last frost dates in Idaho

Typical last frost
April 24

That is the date for the typical Idaho resident, weighted by city population. Across the state the average last frost runs from April 6 to May 12, so look up your own town below.

Earliest city
Apr 6
Latest city
May 12
Typical first frost
Oct 18
Cities
16
This week in Idaho

Frost in the forecast for 7 of 16 cities

National Weather Service forecast, updated Oct 22, 11:10 UTC

Apr 1May 1Apr 15May 15NSBoise City: Apr 24Boise CityMeridian: Apr 24Nampa: Apr 29Caldwell: Apr 29Idaho Falls: May 9Idaho FallsPocatello: May 2PocatelloCoeur d'Alene: Apr 22Coeur d'AleneTwin Falls: Apr 30Post Falls: Apr 22Rexburg: May 12Lewiston: Apr 6Eagle: Apr 29Kuna: Apr 24Star: Apr 29Ammon: May 9
Each dot is a city: further right means a later last frost, higher up means further north. Bigger dots are bigger cities.

Frost dates by city

CityLast frostSafe afterFirst frostSeason
Boise CityApr 24May 9Oct 21179 days
MeridianApr 24May 9Oct 21179 days
NampaApr 29May 18Oct 13164 days
CaldwellApr 29May 18Oct 13164 days
Idaho FallsMay 9Jun 2Oct 1142 days
PocatelloMay 2May 18Oct 11161 days
Coeur d'AleneApr 22May 6Oct 18179 days
Twin FallsApr 30May 14Oct 9161 days
Post FallsApr 22May 6Oct 18179 days
RexburgMay 12Jun 2Sep 24132 days
LewistonApr 6Apr 26Oct 26200 days
EagleApr 29May 18Oct 13164 days
KunaApr 24May 9Oct 21179 days
MoscowNo freeze most years
StarApr 29May 18Oct 13164 days
AmmonMay 9Jun 2Oct 1142 days

When to plant in Idaho

Questions

When is the last frost in Idaho?

It depends on where you are. Across the 15 cities we track, the average last frost runs from April 6 to May 12. In Boise City, the largest, it is April 24.

When is the first frost in Idaho?

For a typical resident, around October 18. Higher and more northern towns get it earlier.