Frost dates in Union County, Iowa
The average last spring frost in Union County falls Apr 23 to Apr 28 and the average first fall frost Oct 11 to Oct 17, depending on the ZIP code (50% odds, 32°F, NOAA 1991–2020 normals). USDA hardiness zone 5b. Places: Afton, Arispe, Creston, Cromwell, Shannon City, Thayer. 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 |
|---|---|---|---|---|
| 50254 | Thayer | Apr 23 | Oct 17 | 5b |
| 50801 | Creston | Apr 28 | Oct 11 | 5b |
| 50830 | Afton | Apr 28 | Oct 11 | 5b |
| 50831 | Arispe | Apr 28 | Oct 11 | 5b |
| 50842 | Cromwell | Apr 28 | Oct 11 | 5b |
| 50861 | Shannon City | Apr 28 | Oct 11 | 5b |
Nearby counties
Ringgold County Adair County Taylor County Adams County Clarke County Madison County
All Iowa counties · Download Iowa frost dates (CSV)
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