Last frost date in O'Fallon, Missouri
April 10
Average last frost in spring. In an early year (1 in 10) it's over by March 26; in a late year (1 in 10) it comes after April 26.
October 26
Average first frost in fall. 1 year in 10 it comes by October 12.
Source: NOAA U.S. Climate Normals 1991–2020, station Weldon Spring NWS (USC00238805), 6.3 miles from O'Fallon, elevation 610 ft. NOAA National Centers for Environmental Information. These are long-term averages, not a forecast.
This station is also the nearest one for Dardenne Prairie, Lake St. Louis and Wentzville, so their frost dates are the same as O'Fallon's.
| Early year | Average | Late year | |
|---|---|---|---|
| Last frost in spring | Mar 26 | Apr 10 | Apr 26 |
| First frost in fall | Oct 12 | Oct 26 | Nov 8 |
Frost-free days in an average year: 199
| Chance in a year | Average last in spring | Average first in fall | |
|---|---|---|---|
| Light frost (36°F) | Every year | Apr 22 | Oct 16 |
| Frost (32°F) | Every year | Apr 10 | Oct 26 |
| Hard freeze (28°F) | Every year | Mar 31 | Nov 5 |
Nights at 32°F or colder in an average year: 105
What to plant now in O'Fallon
- Corn saladSept 15 – Nov 1Now
- Upland cressSept 15 – Nov 1Now
- Rhubarb plantsNov 1 – Dec 1Soon
- Asparagus plantsNov 15 – Jan 1Soon
- Spring planting calendar for an average last frost around April 10 O'Fallon: April 10
- Fall planting calendar for an average first frost around October 30 O'Fallon: October 26
Planting dates: USDA Home and Garden Bulletin No. 9 (1967), “Suburban and Farm Vegetable Gardens,” tables 4 and 5. How we match the table.
Nearby in Missouri
- St. Peters 6 mi · last frost Apr 9
- St. Charles 11 mi · last frost Apr 8
- Chesterfield 12 mi · last frost Apr 4
- Wildwood 15 mi · last frost Apr 12
- Troy 18 mi · last frost Apr 14
Updated