Frost dates · Washington
Washington frost dates,
county by county.
Last spring frost and first fall frost probability data for all 39 counties in Washington, 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 Washington
83 days separate the earliest and latest counties.
The median last spring frost in Grays Harbor County is February 18 — 83 days earlier than Ferry County at May 12. Statewide averages aren't useful planting tools; pick your county below for the data that actually applies to your fields.
By frost timing
Counties sorted by last spring frost.
Latest at top, earliest at bottom. In most states this matches the north-to-south gradient.
- Ferry CountySpring May 12·Fall Sep 24135-day season
- Lincoln CountySpring May 9·Fall Oct 1145-day season
- Pend Oreille CountySpring May 4·Fall Sep 28147-day season
- Chelan CountySpring May 3·Fall Oct 4154-day season
- Klickitat CountySpring May 1·Fall Oct 7159-day season
- Stevens CountySpring Apr 30·Fall Sep 28151-day season
- Adams CountySpring Apr 23·Fall Oct 17177-day season
- Okanogan CountySpring Apr 14·Fall Oct 19188-day season
- Garfield CountySpring Apr 11·Fall Oct 19191-day season
- Kittitas CountySpring Apr 11·Fall Oct 20192-day season
- Franklin CountySpring Apr 10·Fall Oct 24197-day season
- Skamania CountySpring Apr 7·Fall Oct 30206-day season
- Columbia CountySpring Apr 6·Fall Oct 25202-day season
- Grant CountySpring Apr 6·Fall Oct 27204-day season
- Thurston CountySpring Apr 5·Fall Nov 1210-day season
- Whitman CountySpring Apr 5·Fall Oct 20198-day season
- Spokane CountySpring Apr 4·Fall Oct 27206-day season
- Clark CountySpring Mar 29·Fall Nov 5221-day season
- Douglas CountySpring Mar 29·Fall Nov 4220-day season
- Whatcom CountySpring Mar 28·Fall Nov 17234-day season
- Pacific CountySpring Mar 27·Fall Nov 7225-day season
- Wahkiakum CountySpring Mar 25·Fall Nov 12232-day season
- Benton CountySpring Mar 23·Fall Nov 2224-day season
- Snohomish CountySpring Mar 18·Fall Nov 12239-day season
- Pierce CountySpring Mar 16·Fall Nov 14243-day season
- Yakima CountySpring Mar 16·Fall Nov 3232-day season
- Asotin CountySpring Mar 15·Fall Nov 8238-day season
- Cowlitz CountySpring Mar 6·Fall Nov 24263-day season
- Lewis CountySpring Mar 6·Fall Dec 1270-day season
- Clallam CountySpring Mar 4·Fall Nov 24265-day season
- Jefferson CountySpring Mar 4·Fall Nov 24265-day season
- Walla Walla CountySpring Mar 4·Fall Nov 14255-day season
- King CountySpring Feb 27·Fall Nov 29275-day season
- Kitsap CountySpring Feb 27·Fall Nov 30276-day season
- Skagit CountySpring Feb 25·Fall Dec 2280-day season
- San Juan CountySpring Feb 22·Fall Dec 1282-day season
- Island CountySpring Feb 21·Fall Nov 28280-day season
- Mason CountySpring Feb 20·Fall Dec 7290-day season
- Grays Harbor CountySpring Feb 18·Fall Dec 6291-day season
Alphabetical
All Washington counties — A to Z.
- Adams County
- Asotin County
- Benton County
- Chelan County
- Clallam County
- Clark County
- Columbia County
- Cowlitz County
- Douglas County
- Ferry County
- Franklin County
- Garfield County
- Grant County
- Grays Harbor County
- Island County
- Jefferson County
- King County
- Kitsap County
- Kittitas County
- Klickitat County
- Lewis County
- Lincoln County
- Mason County
- Okanogan County
- Pacific County
- Pend Oreille County
- Pierce County
- San Juan County
- Skagit County
- Skamania County
- Snohomish County
- Spokane County
- Stevens County
- Thurston County
- Wahkiakum County
- Walla Walla County
- Whatcom County
- Whitman County
- Yakima County