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: Monday, 23-Mar-2026 04:00 pm

Tonight Mostly Cloudy	Tuesday Mostly Cloudy	Tuesday night Partly Cloudy	Wednesday Mostly Sunny	Wednesday night Partly Cloudy	Thursday Partly Cloudy	Thursday night Chance rain	Friday Chance rain
						<.25 in.	<.1 in.
Low: 37°	High: 61°	Low: 39°	High: 74°	Low: 48°	High: 88°	Low: 50°	High: 56°

E 5-23 mph	ESE 6-21 mph	SE 6-18 mph	S 6-22 mph	SSW 7-16 mph	SSW 11-28 mph	SW→NNE 7-19→11-23 mph	NNE 11-29 mph
	UV: 5 Medium		UV: 7 High		UV: 7 High		UV: 7 High

Tonight	Partly to mostly cloudy in the evening, becoming mostly cloudy after midnight. Low 37°. Wind east around 5 mph, gusting to 23 mph.
Tuesday	Partly to mostly sunny in the morning, becoming partly to mostly cloudy in the afternoon. High 61°. UV index up to 5. Wind east-southeast around 6 mph, gusting to 21 mph.
Tuesday night	Partly to mostly cloudy in the evening, becoming partly cloudy after midnight. Low 39°. Wind southeast around 6 mph, gusting to 18 mph.
Wednesday	Partly to mostly sunny. Warm. High 74°. UV index up to 7. Wind south around 6 mph, gusting to 22 mph.
Wednesday night	Fair to partly cloudy in the evening, becoming mostly clear after midnight. Low 48°. Wind south-southwest around 7 mph, gusting to 16 mph.
Thursday	Sunny in the morning, becoming partly cloudy in the afternoon. Exceptionally hot. High 88°. UV index up to 7. Wind south-southwest around 11 mph, gusting to 28 mph.
Thursday night	Partly cloudy in the evening, becoming cloudy after midnight. A slight chance of rain in the evening, then a chance of rain after midnight. Low 50°. Wind southwest around 7 mph, gusting to 19 mph, in the evening, becoming north-northeast around 11 mph, gusting to 23 mph, after midnight. Chance of precipitation 50 percent. Precipitation mostly less than a quarter of an inch.
Friday	Mostly cloudy in the morning, becoming partly to mostly sunny in the afternoon. A chance of rain in the morning, then a slight chance of rain in the afternoon. Breezy. High 56°. UV index up to 7. Wind north-northeast around 11 mph, gusting to 29 mph. Chance of precipitation 40 percent. Precipitation mostly less than a tenth of an inch.
Friday night	Clear in the evening, becoming fair after midnight. Low 38°. Wind north-northeast around 5 mph, gusting to 25 mph.
Saturday	Sunny. High 59°. UV index up to 7. Wind north-northeast around 3 mph, gusting to 21 mph, in the morning, becoming east-southeast in the afternoon.
Saturday night	Fair to partly cloudy in the evening, becoming partly cloudy after midnight. Low 41°. Wind east-southeast around 5 mph, gusting to 19 mph.
Sunday	Mostly cloudy to cloudy in the morning, becoming mostly cloudy in the afternoon. High 62°. UV index up to 4. Wind south-southeast around 8 mph, gusting to 25 mph.
Sunday night	Mostly cloudy. Low 42°. Wind south-southeast around 6 mph, gusting to 23 mph.

WXSIM forecast formatting script by Saratoga-Weather.org.

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