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-Jul-2026 05:00 am

Today Mostly Sunny	Tonight Fair	Thursday Partly Cloudy	Thursday night Partly Cloudy	Friday Thunder storm	Friday night Thunder storm	Saturday Chance rain	Saturday night Fog late
		<.1 in.		.1 in.	<.25 in.	<.1 in.	<.1 in.
High: 90°	Low: 66°	High: 87°	Low: 69°	High: 84°	Low: 73°	High: 83°	Low: 68°
Heat: 94°
E→NE 5-25 mph	NE 4-23 mph	E 5-23 mph	E→SE 6-20 mph	SE 7-22 mph	S→W 7-20 mph	NW 10-28 mph	NNW 8-25 mph
UV: 9 Very High		UV: 8 Very High		UV: 5 Medium		UV: 6 High

Today	Partly to mostly sunny in the morning, becoming mostly sunny in the afternoon. Hot. High 90°. Heat index up to 94°. UV index up to 9. Wind east around 5 mph, gusting to 25 mph, in the morning, becoming northeast in the afternoon.
Tonight	Fair. Relatively cool. Low 66°. Wind northeast around 4 mph, gusting to 23 mph.
Thursday	Partly to mostly sunny in the morning, becoming partly cloudy in the afternoon. A chance of rain. High 87°. UV index up to 8. Wind east around 5 mph, gusting to 23 mph. Chance of precipitation 30 percent. Precipitation mostly less than a tenth of an inch.
Thursday night	Partly cloudy. Low 69°. Wind east around 6 mph, gusting to 20 mph, in the evening, becoming southeast after midnight.
Friday	Mostly cloudy to cloudy. A slight chance of rain in the morning, then a chance of rain in the afternoon. Scattered thundershowers possible. High 84°. UV index up to 5. Wind southeast around 7 mph, gusting to 22 mph. Chance of precipitation 40 percent. Precipitation mostly around a tenth of an inch.
Friday night	Partly to mostly cloudy in the evening, becoming mostly cloudy to cloudy after midnight. Light to moderate fog in the evening, then patchy light fog after midnight. A chance of rain in the evening, then a slight chance of rain after midnight. Scattered thundershowers possible. Low 73°. Wind south around 7 mph, gusting to 20 mph, in the evening, becoming west after midnight. Chance of precipitation 60 percent. Precipitation mostly less than a quarter of an inch.
Saturday	Mostly cloudy to cloudy in the morning, becoming mostly cloudy in the afternoon. A slight chance of rain in the morning, then a chance of rain in the afternoon. Precipitation showery or intermittent. High 83°. UV index up to 6. Wind northwest around 10 mph, gusting to 28 mph. Chance of precipitation 50 percent. Precipitation mostly less than a tenth of an inch.
Saturday night	Fair to partly cloudy in the evening, becoming mostly clear after midnight. Patchy light fog in the evening, then moderate fog after midnight. A slight chance of rain. Low 68°. Wind north-northwest around 8 mph, gusting to 25 mph. Chance of precipitation 20 percent. Precipitation mostly less than a tenth of an inch.
Sunday	Sunny. Moderate fog in the morning. High 83°. UV index up to 8. Wind north-northeast around 9 mph, gusting to 26 mph.
Sunday night	Mostly clear. Patchy light fog after midnight. Relatively cool. Low 65°. Wind north-northeast around 4 mph, gusting to 23 mph.
Monday	Sunny. Patchy light fog in the morning. High 86°. UV index up to 8. Wind north-northeast around 4 mph, gusting to 23 mph.
Monday night	Clear. Patchy light fog after midnight. Relatively cool. Low 64°. Wind east around 4 mph, gusting to 19 mph.
Tuesday	Sunny. Patchy light fog in the morning. High 89°. Heat index up to 92°. UV index up to 9. Wind southeast around 5 mph, gusting to 23 mph.
Tuesday night	Clear. Patchy light fog after midnight. Low 68°. Wind east around 7 mph, gusting to 22 mph, in the evening, becoming 4 mph after midnight.

WXSIM forecast formatting script by Saratoga-Weather.org.

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