Frost dates in San Juan County, Washington
The average last spring frost in San Juan County falls Feb 26 to Mar 26 and the average first fall frost Nov 10 to Nov 29, depending on the ZIP code (50% odds, 32°F, NOAA 1991–2020 normals). USDA hardiness zone 8b to 9a. Places: Roche Harbor. Pick a ZIP for 10% and 90% odds, soil temperature and the 7-day freeze forecast.
| ZIP | Place | Last spring frost | First fall frost | Zone |
|---|---|---|---|---|
| 98222 | Feb 26 | Nov 29 | 9a | |
| 98243 | Mar 26 | Nov 10 | 9a | |
| 98245 | Feb 26 | Nov 29 | 9a | |
| 98250 | Roche Harbor | Mar 26 | Nov 10 | 9a |
| 98261 | Mar 26 | Nov 10 | 9a | |
| 98279 | Feb 26 | Nov 29 | 8b | |
| 98280 | Feb 26 | Nov 29 | 9a | |
| 98286 | Mar 26 | Nov 10 | 9a | |
| 98297 | Feb 26 | Nov 29 | 9a |
Nearby counties
Whatcom County Island County Skagit County Jefferson County Snohomish County Clallam County
All Washington counties · Download Washington frost dates (CSV)
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