| WXSIM Forecast for:
O'Fallon Issued by: OFallonweather.com |
||||||||||||||||||||||||||||||||||||||||||||||||
| Updated: Friday, 26-Jun-2026 05:00 am | ||||||||||||||||||||||||||||||||||||||||||||||||
|
| Today |
Dense overcast in the morning, becoming mostly cloudy to cloudy in the afternoon. Patchy light fog in the afternoon. Rain likely. Scattered thunderstorms likely. Relatively cool. High 77°. UV index up to 6. Wind south-southeast around 4 mph, gusting to 16 mph, in the morning, becoming southwest in the afternoon. Chance of precipitation 80 percent. Precipitation mostly around half an inch. |
| Tonight |
Partly to mostly cloudy in the evening, becoming mostly cloudy after midnight. Patchy light fog. A chance of rain. Scattered thundershowers possible. Low 69°. Wind south-southwest around 3 mph in the evening, becoming north-northwest after midnight. Chance of precipitation 30 percent. Precipitation mostly less than a tenth of an inch. |
| Saturday |
Cloudy in the morning, becoming mostly cloudy to cloudy in the afternoon. Patchy light fog in the morning. A chance of rain. Scattered thunderstorms likely. High 84°. UV index up to 5. Wind east-northeast around 4 mph, gusting to 21 mph, in the morning, becoming east-southeast in the afternoon. Chance of precipitation 30 percent. Precipitation mostly less than a tenth of an inch. |
| Saturday night |
Partly to mostly cloudy in the evening, becoming fair to partly cloudy after midnight. Light to moderate fog after midnight. Low 69°. Wind southeast around 5 mph, gusting to 20 mph. |
| Sunday |
Sunny in the morning, becoming partly to mostly sunny in the afternoon. Light to moderate fog in the morning. Hot. High 93°. Heat index up to 100°. UV index up to 10. Wind south around 8 mph, gusting to 26 mph. |
| Sunday night |
Partly cloudy in the evening, becoming fair to partly cloudy after midnight. Patchy light fog after midnight. Low 71°. Wind south around 6 mph, gusting to 22 mph. |
| Monday |
Partly to mostly sunny. Patchy light fog in the morning. Hot. High 95°. Heat index up to 105°. UV index up to 10. Wind south around 8 mph, gusting to 26 mph. |
| Monday night |
Fair in the evening, becoming partly cloudy after midnight. Patchy light fog after midnight. Low 73°. Wind south around 6 mph, gusting to 21 mph. |
| Tuesday |
Partly to mostly sunny in the morning, becoming sunny in the afternoon. Patchy light fog in the morning. Very hot. High 96°. Heat index up to 108°. UV index up to 9. Wind south-southwest around 6 mph, gusting to 24 mph. |
| Tuesday night |
Clear. Patchy light fog after midnight. Low 73°. Wind south-southwest around 4 mph, gusting to 18 mph. |
| Wednesday |
Sunny. Patchy light fog in the morning. Very hot. High 95°. Heat index up to 108°. UV index up to 9. Wind south-southwest around 4 mph, gusting to 21 mph. |
| Wednesday night |
Clear in the evening, becoming fair after midnight. Light to moderate fog after midnight. Low 74°. Wind south-southeast around 3 mph, gusting to 15 mph. |
| Thursday |
Partly to mostly cloudy in the morning, becoming mostly cloudy in the afternoon. Patchy light fog in the morning, then light to moderate fog in the afternoon. Rain likely in the afternoon. Thunderstorms very likely, some severe. Very hot. High 96°. Heat index up to 107°. UV index up to 8. Wind west around 3 mph, gusting to 19 mph, in the morning, becoming southeast in the afternoon. Chance of precipitation 80 percent. Precipitation mostly around an inch. |
| Thursday night |
Moderate fog. Rain likely in the evening, then a slight chance of rain after midnight. Thunderstorms very likely, some possibly severe. Low 76°. Wind east around 5 mph in the evening, becoming south-southwest after midnight. Chance of precipitation 70 percent. Precipitation mostly around an inch. |
WXSIM forecast formatting script by Saratoga-Weather.org.
Powered by Davis Vantage Pro2
and
CumulusMX
v 4.6.4 (b4128)
MXUI Template v 2.2.6 by
Silver Acorn
Valid HTML5