| WXSIM Forecast for:
O'Fallon Issued by: OFallonweather.com |
||||||||||||||||||||||||||||||||||||||||||||||||
| Updated: Monday, 29-Jun-2026 04:00 pm | ||||||||||||||||||||||||||||||||||||||||||||||||
|
| Tonight |
Partly cloudy in the evening, becoming fair to partly cloudy after midnight. Light to moderate fog after midnight. Low 75°. Wind south around 7 mph, gusting to 26 mph. |
| Tuesday |
Partly to mostly sunny in the morning, becoming sunny in the afternoon. Light to moderate fog in the morning. Very hot. High 97°. Heat index up to 105°. UV index up to 9. Wind south around 7 mph, gusting to 25 mph. |
| Tuesday night |
Clear. Patchy light fog after midnight. Low 73°. Wind south around 5 mph, gusting to 20 mph. |
| Wednesday |
Sunny. Patchy light fog in the morning. Very hot. High 96°. Heat index up to 106°. UV index up to 9. Wind south around 6 mph, gusting to 24 mph. |
| Wednesday night |
Clear in the evening, becoming fair after midnight. Patchy light fog after midnight. Low 75°. Wind south around 6 mph, gusting to 19 mph. |
| Thursday |
Partly to mostly cloudy in the morning, becoming partly cloudy in the afternoon. Patchy light fog in the morning. A slight chance of rain in the afternoon. Scattered thundershowers possible. Hot. High 95°. Heat index up to 107°. UV index up to 9. Wind south around 5 mph, gusting to 23 mph. Chance of precipitation 30 percent. Precipitation mostly less than a tenth of an inch. |
| Thursday night |
Fair to partly cloudy in the evening, becoming partly cloudy after midnight. Patchy light fog in the evening, then moderate fog after midnight. A slight chance of rain. Low 75°. Wind south-southeast around 5 mph, gusting to 18 mph. Chance of precipitation 20 percent. Precipitation mostly less than a tenth of an inch. |
| Friday |
Mostly sunny in the morning, becoming partly cloudy in the afternoon. Moderate fog in the morning. A slight chance of rain in the morning, then a chance of rain in the afternoon. Scattered thundershowers possible. Hot. High 94°. Heat index up to 105°. UV index up to 9. Wind south-southwest around 5 mph, gusting to 20 mph. Chance of precipitation 30 percent. Precipitation mostly less than a tenth of an inch. |
| Friday night |
Partly cloudy in the evening, becoming fair to partly cloudy after midnight. Moderate fog. Low 75°. Wind south around 4 mph. |
| Saturday |
Partly to mostly cloudy. Light to moderate fog in the morning. A chance of rain. Scattered thunderstorms likely. High 89°. Heat index up to 100°. UV index up to 8. Wind south around 3 mph, gusting to 17 mph. Chance of precipitation 50 percent. Precipitation mostly less than a quarter of an inch. |
| Saturday night |
Partly cloudy in the evening, becoming fair after midnight. Light to moderate fog in the evening, then moderate fog after midnight. Low 74°. Wind south-southeast around 2 mph in the evening, becoming south-southwest after midnight. |
| Sunday |
Mostly sunny in the morning, becoming partly to mostly sunny in the afternoon. Moderate fog in the morning. Hot. High 95°. Heat index up to 106°. UV index up to 9. Wind southwest around 4 mph, gusting to 21 mph, in the morning, becoming 7 mph, gusting to 24 mph, in the afternoon. |
| Sunday night |
Mostly cloudy in the evening, becoming fair after midnight. Moderate fog in the evening, then moderate to dense fog after midnight. Rain likely in the evening, then a chance of rain after midnight. Thunderstorms very likely, some possibly severe. Low 75°. Wind east-northeast around 4 mph, gusting to 16 mph, in the evening, becoming south-southwest after midnight. Chance of precipitation 60 percent. Precipitation mostly between a quarter and half 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