Last frost date in Onalaska, WI
Expect the last frost in Onalaska around April 23. Frost after May 6 happens in only one year out of ten. The first fall frost usually arrives about October 17, which leaves 177 frost-free days. An early freeze before October 3 happens one year in ten.
- Safe after (10% risk)
- May 6
- Average first frost
- Oct 17
- Frost-free season
- 177 days
- Hard freeze (28°F) ends
- Apr 12
No frost in the next 7 nights
Later than usual: the average first frost here is October 17.
National Weather Service forecast, updated Oct 22, 12:57 UTC
- ThuOct 2251°
- FriOct 2357°
- SatOct 2454°
- SunOct 2548°
- MonOct 2642°
- TueOct 2741°
- WedOct 2843°
Planting calendar for Onalaska
Windows count forward or back from the average frost dates above. Click a crop for dates across Wisconsin.
TomatoesApr 30–May 14
PumpkinsMay 7–May 21
SunflowersApr 23–May 14
CucumbersMay 7–May 14
CornApr 30–May 14
Sweet potatoesMay 14–May 28
WatermelonMay 7–May 21
Green beansApr 30–May 21
ZucchiniApr 30–May 14
OkraMay 14–May 28
PeppersMay 7–May 21
BasilApr 30–May 14
Butternut squashApr 30–May 14
CantaloupeMay 7–May 21
EggplantMay 7–May 21
PotatoesMar 26–Apr 9
OnionsMar 12–Apr 2
CarrotsApr 2–May 7
LettuceApr 9–Apr 30
BroccoliMar 26–Apr 9
BeetsMar 26–May 7
PeasMar 12–Mar 26
CabbageMar 26–Apr 9
RadishesMar 19–Apr 30
Brussels sproutsApr 9–Apr 23
SpinachMar 12–Apr 2
CilantroApr 9–Apr 30
KaleMar 26–Apr 9
Collard greensMar 26–Apr 9
TurnipsMar 26–Apr 9
DillApr 23–May 7
CeleryApr 30–May 7
CauliflowerApr 9–Apr 23
LeeksApr 9–Apr 23
Swiss chardApr 9–May 7
ParsleyApr 9–Apr 30
Tulip bulbsOct 3–Nov 7
GarlicSep 26–Oct 31
Daffodil bulbsSep 19–Oct 31
StrawberriesMar 26–Apr 9
AsparagusMar 26–Apr 9Frost probabilities
| Threshold | Spring, 90% chance later | Spring, 50% | Spring, 10% | Fall, 10% chance earlier | Fall, 50% | Fall, 90% |
|---|---|---|---|---|---|---|
| Light frost, 32°F | Apr 9 | Apr 23 | May 6 | Oct 3 | Oct 17 | Nov 1 |
| Hard freeze, 28°F | Mar 31 | Apr 12 | Apr 27 | Oct 15 | Oct 28 | Nov 11 |
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 La Crosse Municipal Airport (USW00014920) sits 2.5 miles from the center of Onalaska at 652 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 Onalaska, WI?
The average last frost date in Onalaska is April 23, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after May 6.
When is the first frost in Onalaska?
The first frost in fall usually comes around October 17. One year in ten it arrives before October 3.
How long is the growing season in Onalaska?
About 177 days between the average last and first frost.
When should I plant tomatoes in Onalaska?
Plant tomato seedlings outside from April 30 to May 14. Start seeds indoors six to eight weeks earlier.
Nearby in Wisconsin
- La CrosseApr 27
- Eau ClaireApr 24
- Stevens PointMay 4
- MiddletonApr 28
- MadisonMay 1
- WausauMay 6
- FitchburgMay 1
- Sun PrairieMay 1
- OshkoshApr 24
- WatertownApr 28
- NeenahMay 4
- Fond du LacApr 27