Last frost date in Beloit, WI
Expect the last frost in Beloit around May 1. Frost after May 16 happens in only one year out of ten. The first fall frost usually arrives about October 12, which leaves 162 frost-free days. An early freeze before September 28 happens one year in ten.
- Safe after (10% risk)
- May 16
- Average first frost
- Oct 12
- Frost-free season
- 162 days
- Hard freeze (28°F) ends
- Apr 20
No frost in the next 7 nights
Later than usual: the average first frost here is October 12.
National Weather Service forecast, updated Oct 22, 12:57 UTC
- ThuOct 2247°
- FriOct 2348°
- SatOct 2451°
- SunOct 2550°
- MonOct 2645°
- TueOct 2742°
- WedOct 2843°
Planting calendar for Beloit
Windows count forward or back from the average frost dates above. Click a crop for dates across Wisconsin.
Frost probabilities
| Threshold | Spring, 90% chance later | Spring, 50% | Spring, 10% | Fall, 10% chance earlier | Fall, 50% | Fall, 90% |
|---|---|---|---|---|---|---|
| Light frost, 32°F | Apr 17 | May 1 | May 16 | Sep 28 | Oct 12 | Oct 24 |
| Hard freeze, 28°F | Apr 4 | Apr 20 | May 4 | Oct 9 | Oct 23 | Nov 4 |
Read the spring 10% column as the date after which only one year in ten still gets frost. That is the safer date for tomatoes, peppers and basil.
Where these numbers come from
NOAA station Beloit (USC00470696) sits 1.5 miles from the center of Beloit at 788 feet. Its averages cover 1991 to 2020. Low spots, valleys and open fields can keep getting frost a week or two after the station stops; city centers and lakeshores usually get less of it.
Questions
When is the last frost in Beloit, WI?
The average last frost date in Beloit is May 1, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after May 16.
When is the first frost in Beloit?
The first frost in fall usually comes around October 12. One year in ten it arrives before September 28.
How long is the growing season in Beloit?
About 162 days between the average last and first frost.
When should I plant tomatoes in Beloit?
Plant tomato seedlings outside from May 8 to May 22. Start seeds indoors six to eight weeks earlier.
Nearby in Wisconsin
- JanesvilleApr 26
- FitchburgMay 1
- MadisonMay 1
- Sun PrairieMay 1
- MiddletonApr 28
- OconomowocApr 30
- WatertownApr 28
- MuskegoMay 3
- WaukeshaMay 1
- New BerlinMay 3
- FranklinMay 3
- Pleasant PrairieApr 19