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Hazardous Weather Conditions

Current conditions at

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Fair

82°F

28°C

Humidity 72%
Wind Speed Vrbl 5 mph
Barometer 29.98 in (1014.8 mb)
Dewpoint 72°F (22°C)
Visibility 10.00 mi
Heat Index87°F (31°C)
Last update 25 Jun 10:53 am CDT
Extended Forecast for

O'Fallon IL

Flood Watch June 25, 01:00pm until June 26, 07:00am
Click here for hazard details and duration
Flood Watch

  • Today

    Today: A 40 percent chance of showers and thunderstorms, mainly after 2pm. Partly sunny, with a high near 85. Light and variable wind.

    High: 85 °F

    Chance
    T-storms

  • Tonight

    Tonight: A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 1am. Some of the storms could produce heavy rainfall. Low around 69. Calm wind becoming southeast around 6 mph after midnight. Chance of precipitation is 80%.

    Low: 69 °F

    Heavy Rain
    then Showers

  • Friday

    Friday: Showers and thunderstorms, mainly before 4pm. High near 82. South wind 8 to 10 mph. Chance of precipitation is 80%.

    High: 82 °F

    Showers then
    T-storms
    Likely

  • Friday Night

    Friday Night: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 7pm. Increasing clouds, with a low around 70. Southwest wind 5 to 8 mph becoming calm in the evening. Chance of precipitation is 70%.

    Low: 70 °F

    Showers
    Likely

  • Saturday

    Saturday: A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 87. Calm wind becoming southwest around 5 mph in the morning.

    High: 87 °F

    Chance
    T-storms

  • Saturday Night

    Saturday Night: A 20 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 73.

    Low: 73 °F

    Slight Chance
    T-storms

  • Sunday

    Sunday: Sunny, with a high near 94.

    High: 94 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 75.

    Low: 75 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 95.

    High: 95 °F

    Sunny

Detailed Forecast

Today
A 40 percent chance of showers and thunderstorms, mainly after 2pm. Partly sunny, with a high near 85. Light and variable wind.
Tonight
A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 1am. Some of the storms could produce heavy rainfall. Low around 69. Calm wind becoming southeast around 6 mph after midnight. Chance of precipitation is 80%.
Friday
Showers and thunderstorms, mainly before 4pm. High near 82. South wind 8 to 10 mph. Chance of precipitation is 80%.
Friday Night
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 7pm. Increasing clouds, with a low around 70. Southwest wind 5 to 8 mph becoming calm in the evening. Chance of precipitation is 70%.
Saturday
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 87. Calm wind becoming southwest around 5 mph in the morning.
Saturday Night
A 20 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 73.
Sunday
Sunny, with a high near 94.
Sunday Night
Mostly clear, with a low around 75.
Monday
Sunny, with a high near 95.
Monday Night
Clear, with a low around 77.
Tuesday
Sunny, with a high near 96.
Tuesday Night
Clear, with a low around 76.
Wednesday
Sunny, with a high near 96.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
O'Fallon IL
 38.59°N 89.92°W (Elev. 551 ft)
Last Update:
10:26 am CDT Jun 25, 2026
Forecast Valid:
11am CDT Jun 25, 2026-6pm CDT Jul 1, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation