National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Fair

72°F

22°C

Humidity 97%
Wind Speed Calm
Barometer 29.89 in (1011.7 mb)
Dewpoint 71°F (22°C)
Visibility 10.00 mi
Last update 10 Jul 6:53 am CDT
Extended Forecast for

Collinsville IL

  • Today

    Today: A slight chance of showers and thunderstorms between 4pm and 5pm. Partly sunny, with a high near 90. Light and variable wind becoming west around 6 mph in the morning. Chance of precipitation is 20%.

    High: 90 °F

    Partly Sunny
    then Slight
    Chance
    T-storms

  • Tonight

    Tonight: Showers and thunderstorms likely before 1am, then showers likely and possibly a thunderstorm between 1am and 2am, then a chance of showers and thunderstorms after 2am. Mostly cloudy, with a low around 72. Southwest wind around 5 mph becoming calm in the evening. Chance of precipitation is 70%.

    Low: 72 °F

    T-storms
    Likely then
    Showers
    Likely

  • Saturday

    Saturday: A 50 percent chance of showers and thunderstorms, mainly after noon. Partly sunny, with a high near 86. Calm wind becoming northwest around 5 mph in the morning.

    High: 86 °F

    Chance
    Showers then
    Chance
    T-storms

  • Saturday Night

    Saturday Night: A slight chance of showers and thunderstorms, then a chance of showers after 7pm. Partly cloudy, with a low around 70. North wind around 6 mph becoming calm in the evening. Chance of precipitation is 30%.

    Low: 70 °F

    Slight Chance
    T-storms then
    Chance
    Showers

  • Sunday

    Sunday: A 20 percent chance of showers after 1pm. Mostly sunny, with a high near 87. Light northeast wind increasing to 5 to 10 mph in the morning.

    High: 87 °F

    Mostly Sunny
    then Slight
    Chance
    Showers

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 69.

    Low: 69 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 89.

    High: 89 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 70.

    Low: 70 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 91.

    High: 91 °F

    Sunny

Detailed Forecast

Today
A slight chance of showers and thunderstorms between 4pm and 5pm. Partly sunny, with a high near 90. Light and variable wind becoming west around 6 mph in the morning. Chance of precipitation is 20%.
Tonight
Showers and thunderstorms likely before 1am, then showers likely and possibly a thunderstorm between 1am and 2am, then a chance of showers and thunderstorms after 2am. Mostly cloudy, with a low around 72. Southwest wind around 5 mph becoming calm in the evening. Chance of precipitation is 70%.
Saturday
A 50 percent chance of showers and thunderstorms, mainly after noon. Partly sunny, with a high near 86. Calm wind becoming northwest around 5 mph in the morning.
Saturday Night
A slight chance of showers and thunderstorms, then a chance of showers after 7pm. Partly cloudy, with a low around 70. North wind around 6 mph becoming calm in the evening. Chance of precipitation is 30%.
Sunday
A 20 percent chance of showers after 1pm. Mostly sunny, with a high near 87. Light northeast wind increasing to 5 to 10 mph in the morning.
Sunday Night
Mostly clear, with a low around 69.
Monday
Sunny, with a high near 89.
Monday Night
Mostly clear, with a low around 70.
Tuesday
Sunny, with a high near 91.
Tuesday Night
Mostly clear, with a low around 72.
Wednesday
Sunny, with a high near 92.
Wednesday Night
Mostly clear, with a low around 74.
Thursday
Sunny, with a high near 93.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Collinsville IL
 38.68°N 90°W (Elev. 499 ft)
Last Update:
6:41 am CDT Jul 10, 2026
Forecast Valid:
7am CDT Jul 10, 2026-6pm CDT Jul 16, 2026
 
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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