Harman US

Frost Dates for Pateros, WA

Last spring frost
Apr 21
First fall frost
Oct 15
Growing season
177 days
Hardiness zone
7a

In an average year around Pateros, WA, the last spring frost (32°F) is about Apr 21 and the first fall frost is about Oct 15, giving roughly a 177-day growing season. To be safe most years, wait until Apr 1 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 - Pateros, WA
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) May 27 May 8 Apr 23
Freeze (32°F) May 10 Apr 21 Apr 1
Hard (28°F) Apr 17 Mar 28 Mar 10
Severe (24°F) Mar 26 Mar 10 Feb 23
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F May 27 May 19 May 15 May 12 May 8 May 5 May 1 Apr 28 Apr 23
32°F May 10 May 3 Apr 30 Apr 25 Apr 21 Apr 17 Apr 13 Apr 8 Apr 1
28°F Apr 17 Apr 8 Apr 3 Mar 31 Mar 28 Mar 24 Mar 20 Mar 15 Mar 10
24°F Mar 26 Mar 20 Mar 16 Mar 13 Mar 10 Mar 7 Mar 4 Mar 1 Feb 23
20°F Mar 15 Mar 10 Mar 6 Mar 2 Feb 28 Feb 24 Feb 21 Feb 16 Feb 10
16°F Mar 7 Feb 28 Feb 25 Feb 20 Feb 16 Feb 12 Feb 8 Feb 2 Jan 26

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 - Pateros, WA
Frost intensity Early (10%) Average (50%) Late (90%)
Light (36°F) Sep 23 Oct 4 Oct 17
Freeze (32°F) Oct 3 Oct 15 Oct 29
Hard (28°F) Oct 10 Oct 26 Nov 10
Severe (24°F) Oct 18 Nov 5 Nov 23
Show full probability table (all thresholds & percentiles)
°F 10% 20% 30% 40% 50% 60% 70% 80% 90%
36°F Sep 23 Sep 28 Oct 1 Oct 2 Oct 4 Oct 6 Oct 9 Oct 12 Oct 17
32°F Oct 3 Oct 6 Oct 9 Oct 12 Oct 15 Oct 17 Oct 21 Oct 24 Oct 29
28°F Oct 10 Oct 16 Oct 21 Oct 24 Oct 26 Oct 28 Nov 1 Nov 5 Nov 10
24°F Oct 18 Oct 26 Oct 30 Nov 1 Nov 5 Nov 9 Nov 13 Nov 18 Nov 23
20°F Oct 28 Nov 2 Nov 9 Nov 13 Nov 18 Nov 21 Nov 25 Nov 29 Dec 5
16°F Nov 2 Nov 12 Nov 19 Nov 24 Nov 28 Dec 2 Dec 7 Dec 13 Dec 20

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: Methow 2 S, Wa, about 6.6 miles away@if(!empty($station['elevation_ft'])), at 1,135 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.

@endif
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 Pateros, WA?

On average, the last spring frost (32°F) around Pateros, WA is about Apr 21. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 1.

When is the first frost in the fall?

The first fall frost around Pateros, WA typically arrives about Oct 15. 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 21 on average, or Apr 1 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 177 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 98846 Planting calendar → Washington frost dates →

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