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: Sunday, 10-May-2026 05:00 am

Today Partly Cloudy	Tonight Fair	Monday Sunny	Monday night Clear	Tuesday Mostly Sunny	Tuesday night Chance rain	Wednesday Fog a.m.	Wednesday night Clear
					.25 in.
High: 73°	Low: 47°	High: 76°	Low: 49°	High: 80°	Low: 56°	High: 77°	Low: 50°

N 6-26 mph	N→SW 1-21 mph	W 4-22 mph	SSW 3-18 mph	S→SW 7-28→11-29 mph	SW→WNW 8-19 mph	NW 9-27 mph	NNW→NE 4-22 mph
UV: 7 High		UV: 7 High		UV: 8 Very High		UV: 7 High

Today	Partly cloudy in the morning, becoming partly to mostly sunny in the afternoon. High 73°. UV index up to 7. Wind north around 6 mph, gusting to 26 mph.
Tonight	Fair. Cool. Low 47°. Wind north around 1 mph, gusting to 21 mph, in the evening, becoming southwest after midnight.
Monday	Sunny. High 76°. UV index up to 7. Wind west around 4 mph, gusting to 22 mph.
Monday night	Clear. Cool. Low 49°. Wind south-southwest around 3 mph, gusting to 18 mph.
Tuesday	Sunny in the morning, becoming mostly sunny in the afternoon. Warm. High 80°. UV index up to 8. Wind south around 7 mph, gusting to 28 mph, in the morning, becoming southwest around 11 mph, gusting to 29 mph, in the afternoon.
Tuesday night	Partly cloudy in the evening, becoming clear after midnight. Moderate fog. A chance of rain. Low 56°. Wind southwest around 8 mph, gusting to 19 mph, in the evening, becoming west-northwest after midnight. Chance of precipitation 50 percent. Precipitation mostly around a quarter of an inch.
Wednesday	Sunny. Patchy light fog in the morning. High 77°. UV index up to 7. Wind northwest around 9 mph, gusting to 27 mph.
Wednesday night	Clear. Cool. Low 50°. Wind north-northwest around 4 mph, gusting to 22 mph, in the evening, becoming northeast after midnight.
Thursday	Sunny. High 77°. UV index up to 8. Wind east-southeast around 4 mph, gusting to 24 mph.
Thursday night	Fair in the evening, becoming partly cloudy after midnight. Cool. Low 53°. Wind southeast around 8 mph, gusting to 22 mph.
Friday	Partly cloudy. Breezy and hot. High 85°. UV index up to 7. Wind south-southeast around 12 mph, gusting to 29 mph.
Friday night	Partly cloudy in the evening, becoming fair to partly cloudy after midnight. Low 55°. Wind south around 7 mph, gusting to 24 mph.
Saturday	Sunny in the morning, becoming mostly sunny in the afternoon. Unusually hot. High 89°. UV index up to 10. Wind south-southwest around 11 mph, gusting to 28 mph.
Saturday night	Partly to mostly cloudy in the evening, becoming mostly cloudy to cloudy after midnight. Patchy light fog in the evening, then light to moderate fog after midnight. Rain likely. Thunderstorms very likely, some possibly severe. Low 62°. Wind south-southwest around 8 mph, gusting to 23 mph, in the evening, becoming west after midnight. Chance of precipitation 70 percent. Precipitation mostly around half an inch.

WXSIM forecast formatting script by Saratoga-Weather.org.

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