| WXSIM Forecast for: 
	   O'Fallon Issued by: OFallonweather.com | ||||||||||||||||||||||||||||||||||||||||||||||||
| Updated: Friday, 31-Oct-2025 05:00 am | ||||||||||||||||||||||||||||||||||||||||||||||||
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| Today | Sunny in the morning, becoming partly cloudy in the afternoon. High 62°. Wind west-southwest around 3 mph, gusting to 24 mph, in the morning, becoming 7 mph, gusting to 24 mph, in the afternoon. | 
| Tonight | Partly to mostly cloudy. Low 42°. Wind west around 4 mph, gusting to 17 mph. | 
| Saturday | Partly to mostly cloudy in the morning, becoming cloudy in the afternoon. A chance of rain. High 55°. Wind west-northwest around 5 mph, gusting to 24 mph. Chance of precipitation 30 percent. Precipitation mostly less than a tenth of an inch. | 
| Saturday night | Partly cloudy in the evening, becoming mostly clear after midnight. Patchy light fog after midnight. Low 37°. Wind west-northwest around 4 mph, gusting to 21 mph. | 
| Sunday | Sunny. Patchy light fog in the morning. High 57°. Wind northwest around 2 mph, gusting to 19 mph, in the morning, becoming west-southwest in the afternoon. | 
| Sunday night | Clear. Light to moderate fog after midnight. Low 36°. Wind south around 4 mph. | 
| Monday | Sunny. Light to moderate fog in the morning. High 63°. Wind southwest around 6 mph, gusting to 24 mph, in the morning, becoming west-northwest in the afternoon. | 
| Monday night | Mostly clear in the evening, becoming partly cloudy after midnight. Low 38°. Wind northwest around 2 mph in the evening, becoming north-northeast after midnight. | 
| Tuesday | Partly cloudy in the morning, becoming sunny in the afternoon. Mild. High 65°. Wind south-southeast around 4 mph, gusting to 18 mph, in the morning, becoming 9 mph, gusting to 25 mph, in the afternoon. | 
| Tuesday night | Mostly clear in the evening, becoming partly cloudy after midnight. Low 42°. Wind south around 9 mph, gusting to 18 mph. | 
| Wednesday | Sunny. Warm. High 72°. Wind west-southwest around 9 mph, gusting to 28 mph, in the morning, becoming west-northwest in the afternoon. | 
| Wednesday night | Clear. Low 36°. Wind north-northwest around 3 mph, gusting to 16 mph. | 
| Thursday | Sunny in the morning, becoming partly to mostly sunny in the afternoon. Mild. High 65°. Wind southeast around 3 mph, gusting to 26 mph, in the morning, becoming 10 mph, gusting to 28 mph, in the afternoon. | 
| Thursday night | Mostly clear in the evening, becoming partly cloudy after midnight. Low 43°. Wind southeast around 9 mph, gusting to 21 mph. | 
WXSIM forecast formatting script by Saratoga-Weather.org.