Frost dates in Jefferson County, Wisconsin
The average last spring frost in Jefferson County falls Apr 25 to May 3 and the average first fall frost Oct 9 to Oct 18, depending on the ZIP code (50% odds, 32°F, NOAA 1991–2020 normals). USDA hardiness zone 5a to 5b. Places: Ixonia, Jefferson, Johnson Creek, Lake Koshkonong, Lake Mills, Palmyra. 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 |
|---|---|---|---|---|
| 53036 | Ixonia | Apr 30 | Oct 12 | 5a |
| 53038 | Johnson Creek | Apr 29 | Oct 14 | 5b |
| 53094 | Watertown | Apr 28 | Oct 12 | 5b |
| 53137 | Rome | May 3 | Oct 9 | 5b |
| 53156 | Palmyra | May 3 | Oct 9 | 5b |
| 53178 | Sullivan | May 3 | Oct 9 | 5b |
| 53538 | Lake Koshkonong | Apr 28 | Oct 13 | 5b |
| 53549 | Jefferson | Apr 25 | Oct 18 | 5b |
| 53551 | Lake Mills | Apr 29 | Oct 14 | 5b |
| 53594 | Waterloo | Apr 30 | Oct 9 | 5b |
Nearby counties
Waukesha County Dodge County Rock County Walworth County Washington County Dane County
All Wisconsin counties · Download Wisconsin frost dates (CSV)
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