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: Monday, 06-Jul-2026 05:00 am

Today Mostly Cloudy	Tonight Partly Cloudy	Tuesday Mostly Cloudy	Tuesday night Partly Cloudy	Wednesday Thunder storm	Wednesday night Fog late	Thursday Thunder storm	Thursday night Thunder storm
				<.1 in.		<.1 in.	.1 in.
High: 89°	Low: 69°	High: 88°	Low: 65°	High: 88°	Low: 69°	High: 92°	Low: 74°
						Heat: 98°
N 5-25 mph	N 4-23 mph	NNE 5-25 mph	NE 2-21 mph	SE 2-21 mph	SE 4-16 mph	SW 6-24 mph	SW 3-15 mph
UV: 6 High		UV: 7 High		UV: 6 High		UV: 8 Very High

Today	Partly to mostly cloudy. High 89°. UV index up to 6. Wind north around 5 mph, gusting to 25 mph.
Tonight	Partly cloudy in the evening, becoming mostly cloudy after midnight. Low 69°. Wind north around 4 mph, gusting to 23 mph.
Tuesday	Mostly cloudy to cloudy in the morning, becoming partly to mostly cloudy in the afternoon. High 88°. UV index up to 7. Wind north-northeast around 5 mph, gusting to 25 mph.
Tuesday night	Fair to partly cloudy in the evening, becoming fair after midnight. Relatively cool. Low 65°. Wind northeast around 2 mph, gusting to 21 mph.
Wednesday	Partly to mostly sunny 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. Scattered thundershowers possible. High 88°. UV index up to 6. Wind southeast around 2 mph, gusting to 21 mph. Chance of precipitation 40 percent. Precipitation mostly less than a tenth of an inch.
Wednesday night	Fair in the evening, becoming fair to partly cloudy after midnight. Patchy light fog after midnight. Low 69°. Wind southeast around 4 mph, gusting to 16 mph.
Thursday	Partly to mostly sunny in the morning, becoming partly to mostly cloudy in the afternoon. Patchy light fog in the morning. A slight chance of rain in the morning, then a chance of rain in the afternoon. Scattered thunderstorms likely. Hot. High 92°. Heat index up to 98°. UV index up to 8. Wind southwest around 6 mph, gusting to 24 mph. Chance of precipitation 40 percent. Precipitation mostly less than a tenth of an inch.
Thursday night	Partly cloudy in the evening, becoming mostly cloudy to cloudy after midnight. Patchy light fog in the evening, then light to moderate fog after midnight. A slight chance of rain in the evening, then a chance of rain after midnight. Scattered thunderstorms likely. Low 74°. Wind southwest around 3 mph, gusting to 15 mph. Chance of precipitation 50 percent. Precipitation mostly around a tenth of an inch.
Friday	Mostly cloudy in the morning, becoming partly to mostly cloudy in the afternoon. Patchy light fog in the morning. A chance of rain. Scattered thunderstorms likely. Hot. High 93°. Heat index up to 101°. UV index up to 9. Wind west-southwest around 6 mph, gusting to 25 mph. Chance of precipitation 30 percent. Precipitation mostly less than a tenth of an inch.
Friday night	Fair to partly cloudy in the evening, becoming partly to mostly cloudy after midnight. Patchy light fog after midnight. A slight chance of rain in the evening, then a chance of rain after midnight. Scattered thunderstorms likely. Low 73°. Wind west-southwest around 2 mph, gusting to 20 mph. Chance of precipitation 40 percent. Precipitation mostly less than a tenth of an inch.
Saturday	Partly cloudy. Patchy light fog in the morning. A chance of rain. High 90°. Heat index up to 98°. UV index up to 7. Wind south-southeast around 4 mph, gusting to 23 mph, in the morning, becoming north-northeast around 8 mph, gusting to 26 mph, in the afternoon. Chance of precipitation 40 percent. Precipitation mostly less than a tenth of an inch.
Saturday night	Fair to partly cloudy in the evening, becoming partly to mostly cloudy after midnight. Patchy light fog in the evening, then light to moderate fog after midnight. A chance of rain. Scattered thundershowers possible. Low 73°. Wind north-northeast around 5 mph, gusting to 22 mph, in the evening, becoming 2 mph after midnight. Chance of precipitation 30 percent. Precipitation mostly less than a tenth of an inch.
Sunday	Sunny. Light to moderate fog in the morning. Hot. High 94°. Heat index up to 104°. UV index up to 9. Wind northwest around 2 mph, gusting to 20 mph, in the morning, becoming 5 mph, gusting to 22 mph, in the afternoon.
Sunday night	Clear. Light to moderate fog after midnight. Low 71°. Wind east-northeast around 3 mph, gusting to 19 mph, in the evening, becoming south after midnight.

WXSIM forecast formatting script by Saratoga-Weather.org.

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