Last spring frost
Apr 30
Frost Dates for Pasco, WA
First fall frost
Oct 13
Growing season
166 days
Hardiness zone
7a
In an average year around Pasco, WA, the last spring frost (32°F) is about Apr 30 and the first fall frost is about Oct 13, giving roughly a 166-day growing season. To be safe most years, wait until Apr 15 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.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | May 28 | May 13 | Apr 30 |
| Freeze (32°F) | May 16 | Apr 30 | Apr 15 |
| Hard (28°F) | May 1 | Apr 13 | Mar 24 |
| Severe (24°F) | Apr 11 | Mar 20 | Feb 24 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 28 | May 23 | May 18 | May 15 | May 13 | May 10 | May 6 | May 3 | Apr 30 |
| 32°F | May 16 | May 10 | May 6 | May 2 | Apr 30 | Apr 27 | Apr 24 | Apr 20 | Apr 15 |
| 28°F | May 1 | Apr 27 | Apr 22 | Apr 17 | Apr 13 | Apr 9 | Apr 3 | Mar 31 | Mar 24 |
| 24°F | Apr 11 | Apr 2 | Mar 30 | Mar 25 | Mar 20 | Mar 14 | Mar 9 | Mar 2 | Feb 24 |
| 20°F | Mar 19 | Mar 10 | Mar 5 | Mar 1 | Feb 26 | Feb 22 | Feb 16 | Feb 8 | Jan 31 |
| 16°F | Mar 6 | Feb 28 | Feb 22 | Feb 16 | Feb 10 | Feb 4 | Jan 28 | Jan 17 | Jan 5 |
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.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Sep 19 | Oct 1 | Oct 14 |
| Freeze (32°F) | Sep 29 | Oct 13 | Oct 27 |
| Hard (28°F) | Oct 8 | Oct 23 | Nov 7 |
| Severe (24°F) | Oct 20 | Nov 2 | Nov 21 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 19 | Sep 23 | Sep 27 | Sep 29 | Oct 1 | Oct 4 | Oct 6 | Oct 10 | Oct 14 |
| 32°F | Sep 29 | Oct 3 | Oct 6 | Oct 10 | Oct 13 | Oct 16 | Oct 19 | Oct 22 | Oct 27 |
| 28°F | Oct 8 | Oct 14 | Oct 18 | Oct 21 | Oct 23 | Oct 26 | Oct 29 | Nov 1 | Nov 7 |
| 24°F | Oct 20 | Oct 25 | Oct 28 | Oct 31 | Nov 2 | Nov 6 | Nov 10 | Nov 14 | Nov 21 |
| 20°F | Oct 27 | Nov 1 | Nov 6 | Nov 10 | Nov 13 | Nov 19 | Nov 24 | Dec 1 | Dec 14 |
| 16°F | Nov 2 | Nov 9 | Nov 16 | Nov 23 | Nov 29 | Dec 4 | Dec 14 | Dec 29 | Jan 12 |
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
@endif These dates are computed from the nearest official weather station with long-term records: Sagemoor, Wa, about 5.8 miles away@if(!empty($station['elevation_ft'])), at 595 ft elevation. The further the station and the greater the elevation difference from your yard, the more your local frost timing can vary.
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 Pasco, WA?
On average, the last spring frost (32°F) around Pasco, WA is about Apr 30. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 15.
When is the first frost in the fall?
The first fall frost around Pasco, WA typically arrives about Oct 13. 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 30 on average, or Apr 15 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 166 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 99301 Planting calendar → Washington frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026