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: Wednesday, 29-Apr-2026 04:00 pm

Tonight Partly Cloudy	Thursday Mostly Cloudy	Thursday night Partly Cloudy	Friday Mostly Cloudy	Friday night Mostly Cloudy	Saturday Partly Cloudy	Saturday night Clear	Sunday Mostly Sunny

Low: 43°	High: 67°	Low: 46°	High: 62°	Low: 44°	High: 60°	Low: 40°	High: 71°

NW 7-26→3 mph	SW 4-25 mph	WSW→NNW 6-20 mph	N 6-24 mph	N 3-21 mph	NNW 5-24→9-26 mph	NW→WSW 4-23 mph	SW 8-27→12-28 mph
	UV: 7 High		UV: 6 High		UV: 6 High		UV: 6 High

Tonight	Partly cloudy in the evening, becoming clear after midnight. Cool. Low 43°. Wind northwest around 7 mph, gusting to 26 mph, in the evening, becoming 3 mph after midnight.
Thursday	Mostly sunny in the morning, becoming partly to mostly cloudy in the afternoon. High 67°. UV index up to 7. Wind southwest around 4 mph, gusting to 25 mph.
Thursday night	Cloudy in the evening, becoming partly cloudy after midnight. Cool. Low 46°. Wind west-southwest around 6 mph, gusting to 20 mph, in the evening, becoming north-northwest after midnight.
Friday	Partly to mostly sunny in the morning, becoming partly to mostly cloudy in the afternoon. High 62°. UV index up to 6. Wind north around 6 mph, gusting to 24 mph.
Friday night	Fair in the evening, becoming partly to mostly cloudy after midnight. Cool. Low 44°. Wind north around 3 mph, gusting to 21 mph.
Saturday	Partly to mostly cloudy in the morning, becoming partly cloudy in the afternoon. Cool. High 60°. UV index up to 6. Wind north-northwest around 5 mph, gusting to 24 mph, in the morning, becoming 9 mph, gusting to 26 mph, in the afternoon.
Saturday night	Clear. Unusually cold. Low 40°. Wind northwest around 4 mph, gusting to 23 mph, in the evening, becoming west-southwest after midnight.
Sunday	Sunny in the morning, becoming mostly sunny in the afternoon. High 71°. UV index up to 6. Wind southwest around 8 mph, gusting to 27 mph, in the morning, becoming 12 mph, gusting to 28 mph, in the afternoon.
Sunday night	Partly cloudy in the evening, becoming partly to mostly cloudy after midnight. A chance of rain. Scattered thundershowers possible. Low 51°. Wind southwest around 8 mph, gusting to 24 mph. Chance of precipitation 30 percent. Precipitation mostly less than a tenth of an inch.
Monday	Mostly cloudy. A chance of rain. Scattered thunderstorms likely. High 73°. UV index up to 5. Wind west-southwest around 10 mph, gusting to 27 mph. Chance of precipitation 30 percent. Precipitation mostly less than a tenth of an inch.
Monday night	Fair to partly cloudy in the evening, becoming clear after midnight. Patchy light fog in the evening, then moderate fog after midnight. A chance of rain. Scattered thundershowers possible. Low 54°. Wind west-southwest around 6 mph, gusting to 21 mph. Chance of precipitation 30 percent. Precipitation mostly less than a tenth of an inch.
Tuesday	Partly to mostly cloudy in the morning, becoming dense overcast in the afternoon. Moderate fog in the morning. A slight chance of rain in the morning, then rain likely in the afternoon. Thunderstorms very likely, some severe. High 73°. UV index up to 5. Wind south around 7 mph, gusting to 24 mph. Chance of precipitation 70 percent. Precipitation mostly around a quarter of an inch.
Tuesday night	Dense overcast. Patchy light fog in the evening, then light to moderate fog after midnight. Rain. Thunderstorms very likely, some severe. Low 60°. Wind south-southwest around 7 mph, gusting to 16 mph. Chance of precipitation 90 percent. Precipitation mostly around 3 inches.

WXSIM forecast formatting script by Saratoga-Weather.org.

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