WXSIM Forecast for: O'Fallon
Issued by: OFallonweather.com
Updated: Saturday, 29-Nov-2025 04:00 pm
 
Tonight

Rain and Snow
Rain and Snow
Sunday

Mostly Cloudy
Mostly Cloudy
Sunday
night
Mostly Cloudy
Mostly Cloudy
Monday

Snow
Snow
Monday
night
Snow
Snow
Tuesday

Fog a.m.
Fog a.m.
Tuesday
night
Mostly Clear
Mostly Clear
Wednesday

Mostly Cloudy
Mostly Cloudy
<.1 in. <.1 in. .1 in.
.5 in.
Low: 28° High: 32° Low: 19° High: 28° Low: 18° High: 35° Low: 18° High: 46°
WCh: 20°              
WSW
12-29
mph
W
11-28
mph
NW→NNE
3-22
mph
ESE
2-15
mph
N→NW
2
mph
NW→WSW
3-19
mph
SSE
4
mph
S→SW
5-22
mph

 

Tonight
 
Cloudy. A slight chance of a mix of snow and rain in the evening, then a slight chance of snow after midnight. Breezy. Low 28°. Wind chill ranging from 20 to 30. Wind west-southwest around 12 mph, gusting to 29 mph. Chance of precipitation 20 percent. Precipitation (liquid equivalent) mostly less than a tenth of an inch. Little or no snow accumulation expected.
Sunday
 
Mostly cloudy in the morning, becoming mostly cloudy to cloudy in the afternoon. Breezy and cold. High 32°. Wind chill around 20. Wind west around 11 mph, gusting to 28 mph.
Sunday night
 
Partly to mostly cloudy in the evening, becoming mostly cloudy to cloudy after midnight. Low 19°. Wind northwest around 3 mph, gusting to 22 mph, in the evening, becoming north-northeast after midnight.
Monday
 
Mostly cloudy to cloudy in the morning, becoming dense overcast in the afternoon. A slight chance of snow. High 28°. Wind east-southeast around 2 mph, gusting to 15 mph. Chance of precipitation 20 percent. Precipitation (liquid equivalent) mostly less than a tenth of an inch. Little or no snow accumulation expected.
Monday night
 
Dense overcast in the evening, becoming partly to mostly cloudy after midnight. Patchy light fog. A chance of snow in the evening, then a slight chance of snow after midnight. Cold. Low 18°. Wind north around 2 mph in the evening, becoming northwest after midnight. Chance of precipitation 50 percent. Precipitation (liquid equivalent) mostly around a tenth of an inch. Snow accumulation about half an inch.
Tuesday
 
Mostly cloudy in the morning, becoming partly cloudy in the afternoon. Patchy light fog in the morning. High 35°. Wind northwest around 3 mph, gusting to 19 mph, in the morning, becoming west-southwest in the afternoon.
Tuesday night
 
Mostly clear. Cold. Low 18°. Wind south-southeast around 4 mph.
Wednesday
 
Partly to mostly sunny in the morning, becoming mostly cloudy to cloudy in the afternoon. High 46°. Wind south around 5 mph, gusting to 22 mph, in the morning, becoming southwest in the afternoon.
Wednesday night
 
Cloudy in the evening, becoming mostly cloudy to cloudy after midnight. A slight chance of snow. Low 23°. Wind chill ranging from 17 to 36. Wind northwest around 7 mph, gusting to 23 mph. Chance of precipitation 20 percent. Precipitation (liquid equivalent) mostly less than a tenth of an inch. Snow accumulation about a quarter inch.
Thursday
 
Partly cloudy in the morning, becoming partly to mostly sunny in the afternoon. High 37°. Wind northwest around 6 mph, gusting to 23 mph, in the morning, becoming 3 mph, gusting to 25 mph, in the afternoon.
Thursday night
 
Partly to mostly cloudy in the evening, becoming mostly cloudy to cloudy after midnight. A chance of a mix of snow and sleet after midnight. Low 25°. Wind chill ranging from 19 to 32. Wind east-southeast around 4 mph. Chance of precipitation 30 percent. Precipitation (liquid equivalent) mostly less than a tenth of an inch. Little or no snow or ice (on ground) accumulation expected.
Friday
 
Dense overcast. A mix of sleet, freezing rain, and snow likely in the morning, then a chance of a mix of rain, freezing rain, sleet, and snow in the afternoon. High 34°. Wind south-southeast around 3 mph in the morning, becoming southwest in the afternoon. Chance of precipitation 80 percent. Precipitation (liquid equivalent) mostly between half an inch and one inch. Snow or ice (on ground) accumulation about an inch. Above-ground freezing rain accumulation up to 0.1 inches.
Friday night
 
Cloudy. Patchy light fog after midnight. A slight chance of a mix of rain, sleet, and snow in the evening, then a slight chance of a mix of sleet, freezing rain, rain, and snow after midnight. Low 31°. Wind west-southwest around 2 mph. Chance of precipitation 30 percent. Precipitation (liquid equivalent) mostly less than a tenth of an inch. Little or no snow or ice (on ground) accumulation expected. Little if any freezing rain accumulation.

WXSIM forecast formatting script by Saratoga-Weather.org.

Powered by Davis Vantage Pro2  and   CumulusMX   v 4.5.2 (b4105)   MXUI Template v 2.2.6 by  Silver Acorn     Valid HTML5 USA Weather Finder Badge