Frost dates in Washington County, Oregon
The average last spring frost in Washington County falls Feb 11 to May 8 and the average first fall frost Oct 1 to Dec 5, depending on the ZIP code (50% odds, 32°F, NOAA 1991–2020 normals). USDA hardiness zone 8b to 9a. Places: Aloha, Banks, Beaverton, Bethany, Cherry Grove, Cornelius. 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 |
|---|---|---|---|---|
| 97003 | Aloha | Feb 11 | Dec 5 | 9a |
| 97005 | Beaverton | Feb 11 | Dec 5 | 9a |
| 97006 | Beaverton | Feb 11 | Dec 5 | 8b |
| 97007 | Beaverton | Apr 1 | Nov 6 | 8b |
| 97008 | Beaverton | Apr 1 | Nov 6 | 9a |
| 97062 | Tualatin | Mar 18 | Nov 13 | 9a |
| 97078 | Aloha | Feb 11 | Dec 5 | 8b |
| 97106 | Banks | Apr 16 | Oct 26 | 8b |
| 97109 | May 8 | Oct 1 | 8b | |
| 97113 | Cornelius | Apr 16 | Oct 26 | 8b |
| 97116 | Forest Grove | Apr 16 | Oct 26 | 8b |
| 97117 | Apr 16 | Oct 26 | 8b | |
| 97119 | Cherry Grove | Apr 16 | Oct 26 | 8b |
| 97123 | Hillsboro | Apr 16 | Oct 23 | 8b |
| 97124 | Hillsboro | Apr 16 | Oct 23 | 8b |
| 97125 | Apr 16 | Oct 26 | 8b | |
| 97133 | North Plains | Apr 10 | Nov 2 | 8b |
| 97140 | Sherwood | Mar 21 | Nov 22 | 8b |
| 97144 | May 8 | Oct 1 | 8b | |
| 97223 | Tigard | Apr 1 | Nov 6 | 9a |
| 97224 | Tigard | Apr 1 | Nov 6 | 9a |
| 97225 | Beaverton | Feb 11 | Dec 5 | 8b |
| 97229 | Bethany | Feb 11 | Dec 5 | 8b |
Nearby counties
Multnomah County Yamhill County Columbia County Clackamas County Marion County Tillamook County
All Oregon counties · Download Oregon frost dates (CSV)
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