Last spring frost
Apr 22
Frost Dates for Big Lake, WA
First fall frost
Oct 19
Growing season
181 days
Hardiness zone
8b
In an average year around Big Lake, WA, the last spring frost (32°F) is about Apr 22 and the first fall frost is about Oct 19, giving roughly a 181-day growing season. To be safe most years, wait until Apr 4 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 24 | May 10 | Apr 28 |
| Freeze (32°F) | May 6 | Apr 22 | Apr 4 |
| Hard (28°F) | Apr 15 | Mar 25 | Mar 3 |
| Severe (24°F) | Mar 17 | Feb 26 | Jan 19 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | May 24 | May 19 | May 16 | May 13 | May 10 | May 7 | May 4 | May 2 | Apr 28 |
| 32°F | May 6 | May 2 | Apr 28 | Apr 25 | Apr 22 | Apr 18 | Apr 13 | Apr 9 | Apr 4 |
| 28°F | Apr 15 | Apr 6 | Apr 2 | Mar 30 | Mar 25 | Mar 21 | Mar 15 | Mar 11 | Mar 3 |
| 24°F | Mar 17 | Mar 11 | Mar 5 | Mar 1 | Feb 26 | Feb 21 | Feb 16 | Feb 7 | Jan 19 |
| 20°F | Feb 28 | Feb 23 | Feb 15 | Feb 7 | Jan 31 | Jan 19 | Jan 7 | Dec 30 | Dec 13 |
| 16°F | Feb 17 | Feb 6 | Jan 27 | Jan 14 | Jan 2 | Dec 27 | Dec 18 | Dec 10 | Dec 2 |
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 17 | Oct 2 | Oct 17 |
| Freeze (32°F) | Oct 3 | Oct 19 | Nov 4 |
| Hard (28°F) | Oct 19 | Nov 3 | Nov 23 |
| Severe (24°F) | Oct 31 | Nov 21 | Dec 16 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Sep 17 | Sep 22 | Sep 26 | Sep 30 | Oct 2 | Oct 5 | Oct 8 | Oct 12 | Oct 17 |
| 32°F | Oct 3 | Oct 8 | Oct 12 | Oct 16 | Oct 19 | Oct 23 | Oct 25 | Oct 29 | Nov 4 |
| 28°F | Oct 19 | Oct 25 | Oct 29 | Oct 31 | Nov 3 | Nov 8 | Nov 12 | Nov 17 | Nov 23 |
| 24°F | Oct 31 | Nov 7 | Nov 11 | Nov 16 | Nov 21 | Nov 25 | Nov 30 | Dec 5 | Dec 16 |
| 20°F | Nov 14 | Nov 22 | Nov 27 | Dec 1 | Dec 6 | Dec 13 | Dec 21 | Jan 1 | Jan 18 |
| 16°F | Nov 23 | Nov 30 | Dec 4 | Dec 8 | Dec 16 | Dec 23 | Dec 31 | Jan 11 | Jan 29 |
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: Arlington, Wa, about 10.3 miles away@if(!empty($station['elevation_ft'])), at 100 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 Big Lake, WA?
On average, the last spring frost (32°F) around Big Lake, WA is about Apr 22. In cooler years it can run later, so for a safer bet many gardeners wait until Apr 4.
When is the first frost in the fall?
The first fall frost around Big Lake, WA typically arrives about Oct 19. 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 4 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 181 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 98274 Planting calendar → Washington frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026