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, 20-Sep-2026 05:00 am

Today Partly Cloudy	Tonight Chance rain	Monday Chance rain	Monday night Cloudy	Tuesday Partly Cloudy	Tuesday night Fog late	Wednesday Fog a.m.	Wednesday night Partly Cloudy
	.1 in.	.1 in.		<.1 in.
High: 93°	Low: 68°	High: 75°	Low: 63°	High: 74°	Low: 54°	High: 73°	Low: 52°

NW 3-23 mph	N 3-19 mph	N 4-22 mph	NNE 5-22 mph	NNE 7-25 mph	NNE 6-24 mph	NNE 7-24 mph	NNE 4-20 mph
UV: 6 High				UV: 6 High		UV: 5 Medium

Today	Partly cloudy in the morning, becoming partly to mostly cloudy in the afternoon. Very hot. High 93°. UV index up to 6. Wind northwest around 3 mph, gusting to 23 mph.
Tonight	Mostly cloudy in the evening, becoming cloudy after midnight. A slight chance of rain in the evening, then a chance of rain after midnight. Warm. Low 68°. Wind north around 3 mph, gusting to 19 mph. Chance of precipitation 50 percent. Precipitation mostly around a tenth of an inch.
Monday	Cloudy. Patchy light fog in the morning. A chance of rain in the morning, then a slight chance of rain in the afternoon. High 75°. Wind north around 4 mph, gusting to 22 mph. Chance of precipitation 50 percent. Precipitation mostly around a tenth of an inch.
Monday night	Cloudy. Low 63°. Wind north-northeast around 5 mph, gusting to 22 mph.
Tuesday	Mostly cloudy to cloudy in the morning, becoming partly cloudy in the afternoon. A slight chance of rain. High 74°. UV index up to 6. Wind north-northeast around 7 mph, gusting to 25 mph. Chance of precipitation 20 percent. Precipitation mostly less than a tenth of an inch.
Tuesday night	Fair to partly cloudy. Patchy light fog after midnight. Low 54°. Wind north-northeast around 6 mph, gusting to 24 mph.
Wednesday	Partly to mostly sunny in the morning, becoming partly cloudy in the afternoon. Patchy light fog in the morning. High 73°. UV index up to 5. Wind north-northeast around 7 mph, gusting to 24 mph.
Wednesday night	Fair to partly cloudy. Low 52°. Wind north-northeast around 4 mph, gusting to 20 mph.
Thursday	Partly to mostly cloudy in the morning, becoming partly cloudy in the afternoon. High 74°. UV index up to 5. Wind north-northeast around 5 mph, gusting to 23 mph.
Thursday night	Partly to mostly cloudy in the evening, becoming mostly cloudy to cloudy after midnight. Low 56°. Wind northeast around 4 mph, gusting to 17 mph.
Friday	Dense overcast. A slight chance of rain. High 69°. Wind east-northeast around 4 mph, gusting to 17 mph. Chance of precipitation 20 percent. Precipitation mostly less than a tenth of an inch.
Friday night	Cloudy in the evening, becoming dense overcast after midnight. A slight chance of rain in the evening, then a chance of rain after midnight. Low 58°. Wind northeast around 5 mph, gusting to 16 mph. Chance of precipitation 30 percent. Precipitation mostly less than a tenth of an inch.
Saturday	Dense overcast. A chance of rain in the morning, then a slight chance of rain in the afternoon. High 64°. Wind east around 4 mph, gusting to 16 mph. Chance of precipitation 50 percent. Precipitation mostly less than a quarter of an inch.
Saturday night	Dense overcast. A chance of rain in the evening, then a slight chance of rain after midnight. Low 60°. Wind east around 4 mph, gusting to 16 mph. Chance of precipitation 30 percent. Precipitation mostly less than a tenth of an inch.

WXSIM forecast formatting script by Saratoga-Weather.org.

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