Frost dates in Custer County, Montana
The average last spring frost in Custer County falls May 8 to May 22 and the average first fall frost Sep 15 to Sep 30, depending on the ZIP code (50% odds, 32°F, NOAA 1991–2020 normals). USDA hardiness zone 4a to 4b. Places: Ismay, Miles City. 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 |
|---|---|---|---|---|
| 59301 | Miles City | May 8 | Sep 30 | 4b |
| 59336 | Ismay | May 22 | Sep 15 | 4a |
| 59338 | May 8 | Sep 30 | 4a | |
| 59345 | May 13 | Sep 25 | 4b |
Nearby counties
Prairie County Fallon County Powder River County Rosebud County Wibaux County Carter County
All Montana counties · Download Montana frost dates (CSV)
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