Seattle, WA Frost Dates
The last spring frost in Seattle usually comes around March 8 and the first fall frost around November 23.
| Spring (last) | Fall (first) | |
|---|---|---|
| Frost, 32°F | March 8 | November 23 |
| Hard freeze, 28°F | February 11 | December 11 |
Growing season: about 259 days.
Frequently asked questions
When is the last frost in Seattle, WA?
The median date of the last spring frost (32°F) is March 8. In half of years the last frost comes earlier and in half it comes later, so waiting a week or two past March 8 lowers the risk for tender plants.
When is the first frost in Seattle?
The median date of the first fall frost (32°F) is November 23, and a hard freeze (28°F) usually follows around December 11.
How long is the growing season in Seattle?
About 259 days between the median last spring frost and first fall frost.
NOAA NCEI U.S. Climate Normals 1991-2020, station USW00094290. Median (50% probability) dates. Low spots and valleys can frost later in spring and earlier in fall than the station.