WXSIM Forecast for: O'Fallon
Issued by: OFallonweather.com
Updated: Wednesday, 08-Apr-2026 04:00 pm
 
Tonight

Fair
Fair
Thursday

Mostly Sunny
Mostly Sunny
Thursday
night
Clear
Clear
Friday

Sunny
Sunny
Friday
night
Mostly Clear
Mostly Clear
Saturday

Sunny
Sunny
Saturday
night
Clear
Clear
Sunday

Sunny
Sunny
Low: 49° High: 79° Low: 49° High: 80° Low: 48° High: 80° Low: 48° High: 81°
               
SSW
7-28
mph
SSW
7-25
mph
SSW
5-18→9
mph
SW→NW
7-27
mph
NNE
3-22
mph
E→SSE
5-26
mph
SSE
7-21
mph
SSE
10-27
mph
UV: 6
 High 
UV: 6
 High 
UV: 7
 High 
UV: 7
 High 

 

Tonight
 
Fair. Low 49°. Wind south-southwest around 7 mph, gusting to 28 mph.
Thursday
 
Mostly sunny. Warm. High 79°. UV index up to 6. Wind south-southwest around 7 mph, gusting to 25 mph.
Thursday night
 
Fair in the evening, becoming clear after midnight. Low 49°. Wind south-southwest around 5 mph, gusting to 18 mph, in the evening, becoming 9 mph after midnight.
Friday
 
Sunny. Warm. High 80°. UV index up to 6. Wind southwest around 7 mph, gusting to 27 mph, in the morning, becoming northwest in the afternoon.
Friday night
 
Mostly clear in the evening, becoming clear after midnight. Low 48°. Wind north-northeast around 3 mph, gusting to 22 mph.
Saturday
 
Sunny. Unusually warm. High 80°. UV index up to 7. Wind east around 5 mph, gusting to 26 mph, in the morning, becoming south-southeast in the afternoon.
Saturday night
 
Clear. Low 48°. Wind south-southeast around 7 mph, gusting to 21 mph.
Sunday
 
Sunny. Unusually warm. High 81°. UV index up to 7. Wind south-southeast around 10 mph, gusting to 27 mph.
Sunday night
 
Mostly clear in the evening, becoming clear after midnight. Low 50°. Wind south-southwest around 8 mph, gusting to 23 mph.
Monday
 
Sunny. Breezy and unusually hot. High 82°. UV index up to 8. Wind south-southwest around 10 mph, gusting to 29 mph, in the morning, becoming 15 mph, gusting to 32 mph, in the afternoon.
Monday night
 
Clear. Low 50°. Wind south-southwest around 11 mph, gusting to 27 mph.
Tuesday
 
Sunny. Breezy and unusually hot. High 83°. UV index up to 8. Wind south-southwest around 13 mph, gusting to 31 mph.
Tuesday night
 
Clear. Low 50°. Wind south-southwest around 11 mph, gusting to 27 mph.

WXSIM forecast formatting script by Saratoga-Weather.org.

Powered by Davis Vantage Pro2  and   CumulusMX   v 4.6.4 (b4128)   MXUI Template v 2.2.6 by  Silver Acorn     Valid HTML5 USA Weather Finder Badge