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: Saturday, 18-Apr-2026 05:00 am

Today Mostly Cloudy	Tonight Clear	Sunday Sunny	Sunday night Mostly Clear	Monday Sunny	Monday night Partly Cloudy	Tuesday Mostly Sunny	Tuesday night Partly Cloudy

High: 60°	Low: 40°	High: 64°	Low: 39°	High: 65°	Low: 44°	High: 75°	Low: 47°

NW 13-32 mph	NW→WSW 9-28→5 mph	W 8-28→14-31 mph	N→NE 5-24 mph	ESE 7-26 mph	ESE→S 7-22 mph	S→SW 9-30→14-30 mph	SW 8-24 mph
UV: 7 High		UV: 6 High		UV: 6 High		UV: 6 High

Today	Partly to mostly cloudy in the morning, becoming sunny in the afternoon. Breezy. High 60°. UV index up to 7. Wind northwest around 13 mph, gusting to 32 mph.
Tonight	Clear. Cool. Low 40°. Wind northwest around 9 mph, gusting to 28 mph, in the evening, becoming west-southwest around 5 mph after midnight.
Sunday	Sunny. Breezy. High 64°. UV index up to 6. Wind west around 8 mph, gusting to 28 mph, in the morning, becoming 14 mph, gusting to 31 mph, in the afternoon.
Sunday night	Mostly clear in the evening, becoming clear after midnight. Cool. Low 39°. Wind north around 5 mph, gusting to 24 mph, in the evening, becoming northeast after midnight.
Monday	Sunny. High 65°. UV index up to 6. Wind east-southeast around 7 mph, gusting to 26 mph.
Monday night	Fair in the evening, becoming fair to partly cloudy after midnight. Cool. Low 44°. Wind east-southeast around 7 mph, gusting to 22 mph, in the evening, becoming south after midnight.
Tuesday	Partly to mostly sunny. Breezy and warm. High 75°. UV index up to 6. Wind south around 9 mph, gusting to 30 mph, in the morning, becoming southwest around 14 mph, gusting to 30 mph, in the afternoon.
Tuesday night	Mostly clear in the evening, becoming fair to partly cloudy after midnight. Low 47°. Wind southwest around 8 mph, gusting to 24 mph.
Wednesday	Sunny in the morning, becoming partly cloudy in the afternoon. Warm. High 76°. UV index up to 6. Wind southwest around 8 mph, gusting to 26 mph.
Wednesday night	Clear in the evening, becoming fair after midnight. Low 49°. Wind south around 5 mph, gusting to 18 mph.
Thursday	Partly cloudy in the morning, becoming partly to mostly sunny in the afternoon. Breezy and warm. High 78°. UV index up to 7. Wind south around 9 mph, gusting to 27 mph, in the morning, becoming 16 mph, gusting to 32 mph, in the afternoon.
Thursday night	Mostly cloudy to cloudy. Low 59°. Wind south around 10 mph, gusting to 26 mph.
Friday	Dense overcast in the morning, becoming mostly cloudy to cloudy in the afternoon. Patchy light fog in the afternoon. Rain very likely. Scattered thunderstorms likely. High 66°. UV index up to 5. Wind south-southwest around 9 mph, gusting to 22 mph. Chance of precipitation 80 percent. Precipitation mostly around an inch.
Friday night	Partly cloudy in the evening, becoming clear after midnight. Light to moderate fog in the evening, then patchy light fog after midnight. A chance of rain. Scattered thunderstorms likely. Low 53°. Wind west-northwest around 7 mph, gusting to 22 mph. Chance of precipitation 50 percent. Precipitation mostly less than a quarter of an inch.

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