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Frost Dates for Wilson Creek, WA

Last spring frost
Apr 22
First fall frost
Oct 17
Growing season
175 days
Hardiness zone
6b

In an average year around Wilson Creek, WA, the last spring frost (32°F) is about Apr 22 and the first fall frost is about Oct 17, giving roughly a 175-day growing season. To be safe most years, wait until Apr 8 before setting out tender plants.

Last spring frost

Dates the last frost of spring typically ends. Plant tender crops after the risk has passed for your comfort level.

Last spring frost - Wilson Creek, WA
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 22 May 4 Apr 22
Freeze (32°F) May 6 Apr 22 Apr 8
Hard (28°F) Apr 25 Apr 6 Mar 19
Severe (24°F) Apr 7 Mar 15 Feb 26
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 22 May 15 May 10 May 7 May 4 May 1 Apr 29 Apr 26 Apr 22
32°F May 6 May 1 Apr 29 Apr 25 Apr 22 Apr 19 Apr 16 Apr 13 Apr 8
28°F Apr 25 Apr 19 Apr 13 Apr 10 Apr 6 Apr 4 Mar 31 Mar 27 Mar 19
24°F Apr 7 Apr 1 Mar 28 Mar 22 Mar 15 Mar 11 Mar 7 Mar 3 Feb 26
20°F Mar 19 Mar 11 Mar 5 Mar 1 Feb 27 Feb 22 Feb 17 Feb 12 Feb 4
16°F Mar 4 Feb 27 Feb 23 Feb 17 Feb 12 Feb 7 Feb 2 Jan 26 Jan 12

First fall frost

Dates the first frost of fall typically arrives. Count back by a crop's days-to-maturity to know your planting cutoff.

First fall frost - Wilson Creek, WA
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Sep 22 Oct 5 Oct 17
Freeze (32°F) Oct 3 Oct 17 Oct 28
Hard (28°F) Oct 14 Oct 27 Nov 10
Severe (24°F) Oct 24 Nov 6 Nov 23
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Sep 22 Sep 28 Oct 1 Oct 3 Oct 5 Oct 8 Oct 11 Oct 14 Oct 17
32°F Oct 3 Oct 8 Oct 12 Oct 15 Oct 17 Oct 19 Oct 22 Oct 24 Oct 28
28°F Oct 14 Oct 19 Oct 22 Oct 25 Oct 27 Oct 30 Nov 1 Nov 4 Nov 10
24°F Oct 24 Oct 28 Oct 31 Nov 3 Nov 6 Nov 10 Nov 14 Nov 18 Nov 23
20°F Nov 1 Nov 5 Nov 10 Nov 14 Nov 17 Nov 21 Nov 25 Nov 28 Dec 6
16°F Nov 9 Nov 15 Nov 20 Nov 24 Nov 27 Dec 1 Dec 6 Dec 13 Dec 24

Growing season is measured at 32°F with about 50% probability. Hardiness zone from the 2023 USDA map; frost normals from NOAA 1991-2020.

Where this data comes from

These dates are computed from the nearest official weather station with long-term records: Ephrata Muni Ap, Wa, about 15.5 miles away@if(!empty($station['elevation_ft'])), at 1,252 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.

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How we calculate these dates

Frost and freeze dates come from the NOAA 1991–2020 U.S. Climate Normals, the National Oceanic and Atmospheric Administration's 30-year averages for each weather station. A date shown at the 50% level is the median: in half of years the frost falls on or before it. The 10% and 90% columns show the early and late ends of the range, so you can plant on the odds you're comfortable with. These are long-term averages, not a forecast for this year - always check your local outlook before planting.

Source: NOAA National Centers for Environmental Information, 1991–2020 Climate Normals (public domain). Harman is not affiliated with or endorsed by NOAA.

Frequently asked questions

When is the last frost in Wilson Creek, WA?

On average, the last spring frost (32°F) around Wilson Creek, WA is about Apr 22. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 8.

When is the first frost in the fall?

The first fall frost around Wilson Creek, WA typically arrives about Oct 17. Count back by a crop's days to maturity to find the latest date you can plant it.

When can I plant tomatoes and other tender crops?

Tender crops like tomatoes, peppers and basil are damaged by frost, so wait until the last spring frost has passed - around Apr 22 on average, or Apr 8 to be safe most years.

How long is the growing season here?

The frost-free growing season (between the last spring and first fall 32°F frost) is about 175 days in a typical year.

Are these dates a forecast for this year?

No. They are 30-year averages from the NOAA 1991–2020 Climate Normals, not a prediction for the current year. Use them for planning and always check your local weather forecast before planting or protecting crops.

Local weather for 98853 Planting calendar → Washington frost dates →

Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026