Last spring frost
Mar 13
Frost Dates for Whidbey Island Station, WA
First fall frost
Nov 14
Growing season
244 days
Hardiness zone
8b
In an average year around Whidbey Island Station, WA, the last spring frost (32°F) is about Mar 13 and the first fall frost is about Nov 14, giving roughly a 244-day growing season. To be safe most years, wait until Feb 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.
| Frost intensity | Early (10%) | Average (50%) | Late (90%) |
|---|---|---|---|
| Light (36°F) | Apr 29 | Apr 9 | Mar 22 |
| Freeze (32°F) | Apr 1 | Mar 13 | Feb 20 |
| Hard (28°F) | Mar 12 | Feb 18 | Jan 5 |
| Severe (24°F) | Feb 24 | Jan 24 | Dec 8 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Apr 29 | Apr 21 | Apr 17 | Apr 13 | Apr 9 | Apr 6 | Apr 2 | Mar 29 | Mar 22 |
| 32°F | Apr 1 | Mar 27 | Mar 21 | Mar 17 | Mar 13 | Mar 9 | Mar 3 | Feb 27 | Feb 20 |
| 28°F | Mar 12 | Mar 2 | Feb 27 | Feb 22 | Feb 18 | Feb 13 | Feb 4 | Jan 24 | Jan 5 |
| 24°F | Feb 24 | Feb 16 | Feb 10 | Feb 2 | Jan 24 | Jan 10 | Jan 2 | Dec 23 | Dec 8 |
| 20°F | Feb 16 | Feb 4 | Jan 25 | Jan 9 | Dec 31 | Dec 23 | Dec 15 | Dec 7 | Nov 30 |
| 16°F | Feb 4 | Jan 24 | Jan 16 | Jan 1 | Dec 30 | Dec 24 | Dec 15 | Dec 7 | Nov 30 |
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 6 | Oct 28 | Nov 17 |
| Freeze (32°F) | Oct 26 | Nov 14 | Dec 5 |
| Hard (28°F) | Nov 9 | Dec 1 | Jan 6 |
| Severe (24°F) | Nov 19 | Dec 15 | Feb 2 |
Show full probability table (all thresholds & percentiles)
| °F | 10% | 20% | 30% | 40% | 50% | 60% | 70% | 80% | 90% |
|---|---|---|---|---|---|---|---|---|---|
| 36°F | Oct 6 | Oct 13 | Oct 18 | Oct 24 | Oct 28 | Oct 31 | Nov 3 | Nov 9 | Nov 17 |
| 32°F | Oct 26 | Nov 1 | Nov 6 | Nov 10 | Nov 14 | Nov 19 | Nov 23 | Nov 28 | Dec 5 |
| 28°F | Nov 9 | Nov 16 | Nov 22 | Nov 26 | Dec 1 | Dec 5 | Dec 11 | Dec 21 | Jan 6 |
| 24°F | Nov 19 | Nov 26 | Dec 1 | Dec 7 | Dec 15 | Dec 23 | Jan 1 | Jan 13 | Feb 2 |
| 20°F | Nov 25 | Dec 1 | Dec 7 | Dec 15 | Dec 22 | Dec 30 | Jan 10 | Jan 26 | Feb 9 |
| 16°F | Nov 27 | Dec 6 | Dec 10 | Dec 21 | Dec 27 | Dec 31 | Jan 9 | Jan 19 | Jan 31 |
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: Whidbey Island Nas, Wa, about 0.7 miles away@if(!empty($station['elevation_ft'])), at 47 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 Whidbey Island Station, WA?
On average, the last spring frost (32°F) around Whidbey Island Station, WA is about Mar 13. In cooler years it can run later, so for a safer bet many gardeners wait until Feb 20.
When is the first frost in the fall?
The first fall frost around Whidbey Island Station, WA typically arrives about Nov 14. 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 13 on average, or Feb 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 244 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 98278 Planting calendar → Washington frost dates →
Data source: NOAA 1991–2020 Climate Normals · Page updated Aug 4, 2026