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: Friday, 28-Aug-2026 04:00 pm

Tonight Partly Cloudy	Saturday Mostly Sunny	Saturday night Partly Cloudy	Sunday Mostly Sunny	Sunday night Clear	Monday Mostly Sunny Hot!	Monday night Partly Cloudy	Tuesday Sunny Hot!

Low: 64°	High: 89°	Low: 64°	High: 93°	Low: 67°	High: 97°	Low: 71°	High: 99°
					Heat: 101°		Heat: 105°
ENE→ESE 2-20 mph	SSE 5-23 mph	SSE 5-18 mph	SSE 7-23 mph	SSE 6-17 mph	SSW 6-21 mph	SSW 5 mph	SSW 6-23 mph
	UV: 7 High		UV: 7 High		UV: 8 Very High		UV: 8 Very High

Tonight	Fair in the evening, becoming partly cloudy after midnight. Low 64°. Wind east-northeast around 2 mph, gusting to 20 mph, in the evening, becoming east-southeast after midnight.
Saturday	Partly to mostly sunny. Hot. High 89°. UV index up to 7. Wind south-southeast around 5 mph, gusting to 23 mph.
Saturday night	Partly cloudy in the evening, becoming fair after midnight. Low 64°. Wind south-southeast around 5 mph, gusting to 18 mph.
Sunday	Partly to mostly sunny in the morning, becoming mostly sunny in the afternoon. Very hot. High 93°. UV index up to 7. Wind south-southeast around 7 mph, gusting to 23 mph.
Sunday night	Clear. Low 67°. Wind south-southeast around 6 mph, gusting to 17 mph.
Monday	Mostly sunny in the morning, becoming sunny in the afternoon. Very hot. High 97°. Heat index up to 101°. UV index up to 8. Wind south-southwest around 6 mph, gusting to 21 mph.
Monday night	Fair to partly cloudy in the evening, becoming fair after midnight. Low 71°. Wind south-southwest around 5 mph.
Tuesday	Sunny. Extremely hot. High 99°. Heat index up to 105°. UV index up to 8. Wind south-southwest around 6 mph, gusting to 23 mph.
Tuesday night	Clear. Patchy light fog after midnight. Low 70°. Wind south-southwest around 5 mph.
Wednesday	Sunny. Patchy light fog in the morning. Very hot. High 97°. Heat index up to 105°. UV index up to 8. Wind south-southwest around 6 mph, gusting to 21 mph.
Wednesday night	Clear. Patchy light fog after midnight. Low 71°. Wind south-southwest around 5 mph.
Thursday	Sunny. Very hot. High 98°. Heat index up to 106°. UV index up to 7. Wind southwest around 7 mph, gusting to 19 mph.
Thursday night	Partly cloudy in the evening, becoming clear after midnight. Low 72°. Wind south-southwest around 5 mph.

WXSIM forecast formatting script by Saratoga-Weather.org.

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