WXSIM Forecast for: O'Fallon
Issued by: OFallonweather.com
Updated: Wednesday, 07-Oct-2026 05:00 am
 
Today

Sunny
Sunny
Tonight

Clear
Clear
Thursday

Sunny
Sunny
Thursday
night
Clear
Clear
Friday

Sunny
Sunny
Friday
night
Clear
Clear
Saturday

Partly Cloudy
Partly Cloudy
Saturday
night
Rain likely
Rain likely
.5 in.
High: 87° Low: 52° High: 82° Low: 51° High: 85° Low: 54° High: 84° Low: 60°
               
WSW
6-25
mph
NNW
4-16
mph
ENE→SE
2-20
mph
E→SE
3
mph
SE
6-23
mph
SE
5
mph
SSE
5-18→8-25
mph
E→NE
5-16
mph
UV: 5
 Medium 
UV: 5
 Medium 
UV: 5
 Medium 
UV: 5
 Medium 

 

Today
 
Sunny. Unusually hot. High 87°. UV index up to 5. Wind west-southwest around 6 mph, gusting to 25 mph.
Tonight
 
Clear. Low 52°. Wind north-northwest around 4 mph, gusting to 16 mph.
Thursday
 
Sunny. Unusually hot. High 82°. UV index up to 5. Wind east-northeast around 2 mph, gusting to 20 mph, in the morning, becoming southeast in the afternoon.
Thursday night
 
Clear. Low 51°. Wind east around 3 mph in the evening, becoming southeast after midnight.
Friday
 
Sunny. Unusually hot. High 85°. UV index up to 5. Wind southeast around 6 mph, gusting to 23 mph.
Friday night
 
Clear. Low 54°. Wind southeast around 5 mph.
Saturday
 
Partly cloudy. Unusually hot. High 84°. UV index up to 5. Wind south-southeast around 5 mph, gusting to 18 mph, in the morning, becoming 8 mph, gusting to 25 mph, in the afternoon.
Saturday night
 
Mostly cloudy in the evening, becoming partly cloudy after midnight. Light to moderate fog in the evening, then moderate fog after midnight. Rain likely. Low 60°. Wind east around 5 mph, gusting to 16 mph, in the evening, becoming northeast after midnight. Chance of precipitation 70 percent. Precipitation mostly around half an inch.
Sunday
 
Partly to mostly sunny in the morning, becoming sunny in the afternoon. Patchy light fog in the morning. A slight chance of rain. Warm. High 80°. UV index up to 5. Wind north-northeast around 5 mph, gusting to 25 mph, in the morning, becoming northwest in the afternoon. Chance of precipitation 20 percent. Precipitation mostly less than a tenth of an inch.
Sunday night
 
Clear in the evening, becoming fair to partly cloudy after midnight. Patchy light fog after midnight. Low 58°. Wind south around 3 mph.
Monday
 
Sunny. Patchy light fog in the morning. Unusually hot. High 87°. UV index up to 5. Wind southwest around 7 mph, gusting to 21 mph.
Monday night
 
Fair in the evening, becoming mostly cloudy to cloudy after midnight. Mild. Low 63°. Wind southwest around 4 mph in the evening, becoming west after midnight.
Tuesday
 
Mostly cloudy to cloudy in the morning, becoming partly to mostly cloudy in the afternoon. A slight chance of rain. Warm. High 76°. Wind north-northwest around 7 mph, gusting to 26 mph. Chance of precipitation 20 percent. Precipitation mostly less than a tenth of an inch.
Tuesday night
 
Partly cloudy in the evening, becoming cloudy after midnight. Low 57°. Wind northeast around 9 mph, gusting to 22 mph, in the evening, becoming east after midnight.

WXSIM forecast formatting script by Saratoga-Weather.org.

Powered by Davis Vantage Pro2  and   CumulusMX   v 5.1.6 (b5016)   MXUI Template v 2.2.6 by  Silver Acorn     Valid HTML5 USA Weather Finder Badge