Last spring frost
Mar 20
Frost Dates for Auburn, WA
First fall frost
Nov 10
Growing season
233 days
Hardiness zone
8b
In an average year around Auburn, WA, the last spring frost (32°F) is about Mar 20 and the first fall frost is about Nov 10, giving roughly a 233-day growing season. To be safe most years, wait until Feb 27 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) | Apr 30 | Apr 11 | Mar 26 |
| Freeze (32°F) | Apr 8 | Mar 20 | Feb 27 |
| Hard (28°F) | Mar 16 | Feb 25 | Jan 19 |
| Severe (24°F) | Feb 27 | Jan 24 | Dec 8 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 30 | Apr 24 | Apr 19 | Apr 15 | Apr 11 | Apr 7 | Apr 4 | Mar 31 | Mar 26 |
| 32°F | Apr 8 | Apr 1 | Mar 29 | Mar 24 | Mar 20 | Mar 16 | Mar 12 | Mar 6 | Feb 27 |
| 28°F | Mar 16 | Mar 11 | Mar 5 | Feb 28 | Feb 25 | Feb 20 | Feb 15 | Feb 6 | Jan 19 |
| 24°F | Feb 27 | Feb 19 | Feb 12 | Feb 1 | Jan 24 | Jan 10 | Jan 2 | Dec 20 | Dec 8 |
| 20°F | Feb 9 | Jan 27 | Jan 13 | Jan 3 | Dec 29 | Dec 20 | Dec 12 | Dec 7 | Nov 30 |
| 16°F | Feb 2 | Jan 21 | Jan 1 | Dec 27 | Dec 15 | Dec 9 | Dec 2 | Nov 28 | Nov 19 |
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) | Oct 13 | Oct 27 | Nov 11 |
| Freeze (32°F) | Oct 26 | Nov 10 | Nov 26 |
| Hard (28°F) | Nov 6 | Nov 24 | Dec 20 |
| Severe (24°F) | Nov 16 | Dec 8 | Jan 17 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 13 | Oct 17 | Oct 20 | Oct 24 | Oct 27 | Oct 29 | Nov 1 | Nov 5 | Nov 11 |
| 32°F | Oct 26 | Oct 31 | Nov 3 | Nov 7 | Nov 10 | Nov 13 | Nov 17 | Nov 22 | Nov 26 |
| 28°F | Nov 6 | Nov 11 | Nov 15 | Nov 20 | Nov 24 | Nov 27 | Dec 2 | Dec 8 | Dec 20 |
| 24°F | Nov 16 | Nov 24 | Nov 29 | Dec 4 | Dec 8 | Dec 16 | Dec 24 | Jan 2 | Jan 17 |
| 20°F | Nov 23 | Nov 30 | Dec 5 | Dec 9 | Dec 14 | Dec 25 | Jan 1 | Jan 11 | Jan 30 |
| 16°F | Nov 18 | Nov 26 | Dec 1 | Dec 6 | Dec 11 | Dec 22 | Dec 30 | Jan 7 | 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
@endif These dates are computed from the nearest official weather station with long-term records: Kent, Wa, about 7.6 miles away@if(!empty($station['elevation_ft'])), at 30 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 Auburn, WA?
On average, the last spring frost (32°F) around Auburn, WA is about Mar 20. In cooler years it can run later, so for a safer bet many gardeners wait until Feb 27.
When is the first frost in the fall?
The first fall frost around Auburn, WA typically arrives about Nov 10. 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 Mar 20 on average, or Feb 27 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 233 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 98002 Planting calendar → Washington frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026