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: Friday, 27-Mar-2026 04:00 pm

Tonight Partly Cloudy	Saturday Sunny	Saturday night Partly Cloudy	Sunday Mostly Cloudy	Sunday night Partly Cloudy	Monday Partly Cloudy	Monday night Partly Cloudy	Tuesday Mostly Cloudy
							<.1 in.
Low: 34°	High: 57°	Low: 36°	High: 69°	Low: 43°	High: 80°	Low: 55°	High: 83°

NNW 9-26→5-17 mph	E→SE 5-25 mph	SE 7-22 mph	S 9-27 mph	SSW 8-20 mph	SSW 11-28 mph	SSW 11-22 mph	SSW 12-29 mph
	UV: 7 High		UV: 6 High		UV: 6 High		UV: 5 Medium

Tonight	Fair to partly cloudy in the evening, becoming clear after midnight. Cold. Low 34°. Wind north-northwest around 9 mph, gusting to 26 mph, in the evening, becoming 5 mph, gusting to 17 mph, after midnight.
Saturday	Sunny. High 57°. UV index up to 7. Wind east around 5 mph, gusting to 25 mph, in the morning, becoming southeast in the afternoon.
Saturday night	Clear in the evening, becoming partly cloudy after midnight. Cold. Low 36°. Wind southeast around 7 mph, gusting to 22 mph.
Sunday	Partly to mostly cloudy. Mild. High 69°. UV index up to 6. Wind south around 9 mph, gusting to 27 mph.
Sunday night	Partly cloudy in the evening, becoming clear after midnight. Low 43°. Wind south-southwest around 8 mph, gusting to 20 mph.
Monday	Sunny in the morning, becoming partly cloudy in the afternoon. Unusually warm. High 80°. UV index up to 6. Wind south-southwest around 11 mph, gusting to 28 mph.
Monday night	Partly cloudy in the evening, becoming fair after midnight. Breezy. Low 55°. Wind south-southwest around 11 mph, gusting to 22 mph.
Tuesday	Partly to mostly sunny in the morning, becoming mostly cloudy in the afternoon. A slight chance of rain. Precipitation showery or intermittent. Breezy and unusually hot. High 83°. UV index up to 5. Wind south-southwest around 12 mph, gusting to 29 mph. Chance of precipitation 20 percent. Precipitation mostly less than a tenth of an inch.
Tuesday night	Dense overcast. Patchy light fog. Rain likely. Scattered thundershowers possible. Low 49°. Wind north-northwest around 10 mph, gusting to 27 mph. Chance of precipitation 80 percent. Precipitation mostly around an inch.
Wednesday	Cloudy in the morning, becoming mostly cloudy to cloudy in the afternoon. A slight chance of rain in the morning, then a chance of rain in the afternoon. High 57°. UV index up to 4. Wind north-northeast around 9 mph, gusting to 26 mph. Chance of precipitation 30 percent. Precipitation mostly less than a tenth of an inch.
Wednesday night	Mostly cloudy in the evening, becoming mostly cloudy to cloudy after midnight. Patchy light fog after midnight. Rain likely. Low 42°. Wind northeast around 8 mph, gusting to 21 mph. Chance of precipitation 60 percent. Precipitation mostly around a quarter of an inch.
Thursday	Cloudy in the morning, becoming dense overcast in the afternoon. A chance of rain in the morning, then a slight chance of rain in the afternoon. High 48°. Wind northeast around 7 mph, gusting to 22 mph. Chance of precipitation 50 percent. Precipitation mostly around a tenth of an inch.
Thursday night	Mostly cloudy to cloudy in the evening, becoming mostly clear after midnight. Low 39°. Wind northeast around 4 mph, gusting to 22 mph.

WXSIM forecast formatting script by Saratoga-Weather.org.

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