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: Tuesday, 28-Apr-2026 04:00 pm

Tonight Rain likely	Wednesday Fog a.m.	Wednesday night Partly Cloudy	Thursday Mostly Cloudy	Thursday night Chance rain	Friday Fog a.m.	Friday night Partly Cloudy	Saturday Partly Cloudy
.35 in.				<.1 in.
Low: 47°	High: 62°	Low: 39°	High: 64°	Low: 45°	High: 57°	Low: 39°	High: 58°

NNE 6-20 mph	NNW 9-26 mph	NNW 4-21 mph	W 2-20→5-22 mph	N 3-18 mph	N 8-24 mph	NNE 4-20 mph	NW 4-23→9-24 mph
	UV: 5 Medium		UV: 6 High		UV: 5 Medium		UV: 6 High

Tonight	Mostly cloudy to cloudy in the evening, becoming fair to partly cloudy after midnight. Moderate fog in the evening, then light to moderate fog after midnight. Rain likely in the evening, then a slight chance of rain after midnight. Cool. Low 47°. Wind north-northeast around 6 mph, gusting to 20 mph. Chance of precipitation 70 percent. Precipitation mostly between a quarter and half an inch.
Wednesday	Sunny in the morning, becoming partly to mostly cloudy in the afternoon. Patchy light fog in the morning. High 62°. UV index up to 5. Wind north-northwest around 9 mph, gusting to 26 mph.
Wednesday night	Partly cloudy in the evening, becoming clear after midnight. Cool. Low 39°. Wind north-northwest around 4 mph, gusting to 21 mph.
Thursday	Mostly sunny in the morning, becoming mostly cloudy in the afternoon. High 64°. UV index up to 6. Wind west around 2 mph, gusting to 20 mph, in the morning, becoming 5 mph, gusting to 22 mph, in the afternoon.
Thursday night	Mostly cloudy to cloudy. Patchy light fog after midnight. A slight chance of rain in the evening, then a chance of rain after midnight. Cool. Low 45°. Wind north around 3 mph, gusting to 18 mph. Chance of precipitation 40 percent. Precipitation mostly less than a tenth of an inch.
Friday	Partly cloudy in the morning, becoming partly to mostly cloudy in the afternoon. Patchy light fog in the morning. Cool. High 57°. UV index up to 5. Wind north around 8 mph, gusting to 24 mph.
Friday night	Partly cloudy in the evening, becoming mostly clear after midnight. Cool. Low 39°. Wind north-northeast around 4 mph, gusting to 20 mph.
Saturday	Sunny in the morning, becoming partly cloudy in the afternoon. Cool. High 58°. UV index up to 6. Wind northwest around 4 mph, gusting to 23 mph, in the morning, becoming 9 mph, gusting to 24 mph, in the afternoon.
Saturday night	Clear. Cool. Low 41°. Wind north-northwest around 4 mph, gusting to 20 mph, in the evening, becoming southwest after midnight.
Sunday	Sunny in the morning, becoming partly to mostly sunny in the afternoon. High 67°. UV index up to 6. Wind southwest around 8 mph, gusting to 26 mph.
Sunday night	Partly to mostly cloudy. A chance of rain. Low 50°. Wind southwest around 6 mph, gusting to 18 mph. Chance of precipitation 30 percent. Precipitation mostly less than a tenth of an inch.
Monday	Sunny in the morning, becoming mostly sunny in the afternoon. High 70°. UV index up to 9. Wind west-northwest around 6 mph, gusting to 23 mph, in the morning, becoming north-northwest in the afternoon.
Monday night	Mostly cloudy in the evening, becoming partly cloudy after midnight. A slight chance of rain. Low 51°. Wind north-northeast around 4 mph, gusting to 17 mph, in the evening, becoming southeast after midnight. Chance of precipitation 20 percent. Precipitation mostly less than a tenth of an inch.

WXSIM forecast formatting script by Saratoga-Weather.org.

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