Frost dates in Custer County, Idaho
The average last spring frost in Custer County falls May 14 to Jun 14 and the average first fall frost Sep 6 to Sep 25, depending on the ZIP code (50% odds, 32°F, NOAA 1991–2020 normals). USDA hardiness zone 5a to 5b. Places: Challis, Clayton, Mackay, Stanley. 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 |
|---|---|---|---|---|
| 83226 | Challis | May 14 | Sep 25 | 5b |
| 83227 | Clayton | May 14 | Sep 25 | 5b |
| 83235 | Jun 12 | Sep 6 | 5b | |
| 83251 | Mackay | Jun 14 | Sep 8 | 5a |
| 83278 | Stanley | May 21 | Sep 18 | 5b |
Nearby counties
Blaine County Lemhi County Butte County Camas County Boise County Valley County
All Idaho counties · Download Idaho frost dates (CSV)
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