OFallon Missouri Weather

OFallon - Weather Data from OFallon, MO

Latitude: N 38° 50' 20" Longitude: W 90° 43' 42" Altitude: 532 ft

CDT UTC Last station update CDT

WXSIM Forecast for: O'Fallon
Issued by: OFallonweather.com

Updated: Thursday, 01-Oct-2026 04:00 pm

Tonight Rain likely	Friday Mostly Cloudy	Friday night Fog late	Saturday Fog a.m.	Saturday night Fog late	Sunday Fog a.m.	Sunday night Fog late	Monday Fog a.m.
.25 in.
Low: 64°	High: 74°	Low: 50°	High: 75°	Low: 50°	High: 76°	Low: 49°	High: 73°

WNW→N 6-20→9-23 mph	N 9-27 mph	NNE 6-22 mph	NE 4-23 mph	NE→NW calm	NW→N 4-22 mph	N 5-16 mph	NNE 5-24 mph
	UV: 6 High		UV: 6 High		UV: 5 Medium		UV: 5 Medium

Tonight	Dense overcast. Light to moderate fog in the evening, then patchy light fog after midnight. Rain likely. Mild. Low 64°. Wind west-northwest around 6 mph, gusting to 20 mph, in the evening, becoming north around 9 mph, gusting to 23 mph, after midnight. Chance of precipitation 60 percent. Precipitation mostly around a quarter of an inch.
Friday	Mostly cloudy in the morning, becoming sunny in the afternoon. High 74°. UV index up to 6. Wind north around 9 mph, gusting to 27 mph.
Friday night	Clear. Patchy light fog after midnight. Low 50°. Wind north-northeast around 6 mph, gusting to 22 mph.
Saturday	Sunny in the morning, becoming mostly sunny in the afternoon. Patchy light fog in the morning. High 75°. UV index up to 6. Wind northeast around 4 mph, gusting to 23 mph.
Saturday night	Partly cloudy in the evening, becoming fair to partly cloudy after midnight. Patchy light fog after midnight. Low 50°. Wind northeast near calm in the evening, becoming northwest after midnight.
Sunday	Sunny. Patchy light fog in the morning. Warm. High 76°. UV index up to 5. Wind northwest around 4 mph, gusting to 22 mph, in the morning, becoming north in the afternoon.
Sunday night	Clear. Patchy light fog after midnight. Low 49°. Wind north around 5 mph, gusting to 16 mph.
Monday	Sunny. Patchy light fog in the morning. High 73°. UV index up to 5. Wind north-northeast around 5 mph, gusting to 24 mph.
Monday night	Clear. Patchy light fog after midnight. Low 47°. Wind northeast around 3 mph, gusting to 16 mph, in the evening, becoming east after midnight.
Tuesday	Sunny. Patchy light fog in the morning. Warm. High 76°. UV index up to 5. Wind southeast around 4 mph, gusting to 23 mph.
Tuesday night	Fair to partly cloudy. Low 50°. Wind south-southeast around 4 mph.
Wednesday	Partly cloudy in the morning, becoming partly to mostly sunny in the afternoon. Warm. High 80°. UV index up to 5. Wind southwest around 5 mph, gusting to 17 mph, in the morning, becoming 8 mph, gusting to 24 mph, in the afternoon.
Wednesday night	Fair to partly cloudy in the evening, becoming fair after midnight. Low 49°. Wind north-northwest around 5 mph.

WXSIM forecast formatting script by Saratoga-Weather.org.

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