Harman US

Frost Dates for Uniontown, WA

Last spring frost
Apr 6
First fall frost
Oct 26
Growing season
200 days
Hardiness zone
7a

In an average year around Uniontown, WA, the last spring frost (32°F) is about Apr 6 and the first fall frost is about Oct 26, giving roughly a 200-day growing season. To be safe most years, wait until Mar 20 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 - Uniontown, WA
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 12 Apr 29 Apr 11
Freeze (32°F) Apr 26 Apr 6 Mar 20
Hard (28°F) Apr 4 Mar 15 Feb 25
Severe (24°F) Mar 19 Feb 27 Jan 27
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 12 May 7 May 3 May 1 Apr 29 Apr 25 Apr 21 Apr 17 Apr 11
32°F Apr 26 Apr 19 Apr 14 Apr 10 Apr 6 Apr 3 Mar 31 Mar 27 Mar 20
28°F Apr 4 Mar 30 Mar 26 Mar 20 Mar 15 Mar 11 Mar 6 Mar 2 Feb 25
24°F Mar 19 Mar 10 Mar 5 Mar 1 Feb 27 Feb 22 Feb 16 Feb 8 Jan 27
20°F Mar 5 Feb 28 Feb 22 Feb 16 Feb 9 Feb 1 Jan 24 Jan 13 Jan 1
16°F Feb 27 Feb 17 Feb 8 Jan 31 Jan 23 Jan 13 Jan 4 Dec 28 Dec 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 - Uniontown, WA
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Oct 1 Oct 13 Oct 28
Freeze (32°F) Oct 10 Oct 26 Nov 12
Hard (28°F) Oct 20 Nov 8 Nov 28
Severe (24°F) Oct 30 Nov 23 Dec 13
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Oct 1 Oct 5 Oct 7 Oct 10 Oct 13 Oct 15 Oct 18 Oct 23 Oct 28
32°F Oct 10 Oct 14 Oct 18 Oct 23 Oct 26 Oct 29 Nov 1 Nov 5 Nov 12
28°F Oct 20 Oct 27 Nov 1 Nov 4 Nov 8 Nov 13 Nov 18 Nov 23 Nov 28
24°F Oct 30 Nov 7 Nov 13 Nov 19 Nov 23 Nov 26 Nov 30 Dec 6 Dec 13
20°F Nov 10 Nov 20 Nov 26 Nov 30 Dec 5 Dec 9 Dec 15 Dec 23 Jan 3
16°F Nov 23 Nov 30 Dec 5 Dec 10 Dec 16 Dec 24 Dec 31 Jan 9 Jan 28

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: Lewiston Nez Perce Co Ap, Id, about 9.8 miles away@if(!empty($station['elevation_ft'])), at 1,436 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 Uniontown, WA?

On average, the last spring frost (32°F) around Uniontown, WA is about Apr 6. In cooler years it can run later, so for a safer bet many gardeners wait until Mar 20.

When is the first frost in the fall?

The first fall frost around Uniontown, WA typically arrives about Oct 26. 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 6 on average, or Mar 20 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 200 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 99179 Planting calendar → Washington frost dates →

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