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

Hazardous Weather Conditions

Current conditions at

St. Louis Downtown Airport (KCPS)

Lat: 38.56°NLon: 90.15°WElev: 410ft.

Mostly Cloudy

52°F

11°C

Humidity 83%
Wind Speed Calm
Barometer 29.88 in (1011.6 mb)
Dewpoint 47°F (8°C)
Visibility 10.00 mi
Last update 21 Mar 3:53 am CDT
Extended Forecast for

Cahokia IL

  • Today

    Today: Sunny, with a high near 89. Calm wind becoming south around 6 mph in the afternoon.

    High: 89 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 64. Southwest wind 5 to 7 mph.

    Low: 64 °F

    Mostly Clear

  • Sunday

    Sunday: Mostly sunny, with a high near 90. Southwest wind 7 to 14 mph becoming northwest in the afternoon. Winds could gust as high as 23 mph.

    High: 90 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: A slight chance of showers and thunderstorms before 10pm, then a slight chance of showers between 10pm and 1am. Partly cloudy, with a low around 40. North wind 10 to 18 mph, with gusts as high as 31 mph. Chance of precipitation is 20%.

    Low: 40 °F

    Slight Chance
    T-storms then
    Slight Chance
    Showers

  • Monday

    Monday: Mostly sunny, with a high near 59. Northeast wind around 8 mph.

    High: 59 °F

    Mostly Sunny

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 42.

    Low: 42 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Partly sunny, with a high near 63.

    High: 63 °F

    Partly Sunny

  • Tuesday Night

    Tuesday Night: A 20 percent chance of showers after 1am. Mostly cloudy, with a low around 45.

    Low: 45 °F

    Mostly Cloudy
    then Slight
    Chance
    Showers

  • Wednesday

    Wednesday: A 20 percent chance of showers and thunderstorms before 1pm. Partly sunny, with a high near 73.

    High: 73 °F

    Slight Chance
    T-storms

Detailed Forecast

Today
Sunny, with a high near 89. Calm wind becoming south around 6 mph in the afternoon.
Tonight
Mostly clear, with a low around 64. Southwest wind 5 to 7 mph.
Sunday
Mostly sunny, with a high near 90. Southwest wind 7 to 14 mph becoming northwest in the afternoon. Winds could gust as high as 23 mph.
Sunday Night
A slight chance of showers and thunderstorms before 10pm, then a slight chance of showers between 10pm and 1am. Partly cloudy, with a low around 40. North wind 10 to 18 mph, with gusts as high as 31 mph. Chance of precipitation is 20%.
Monday
Mostly sunny, with a high near 59. Northeast wind around 8 mph.
Monday Night
Mostly cloudy, with a low around 42.
Tuesday
Partly sunny, with a high near 63.
Tuesday Night
A 20 percent chance of showers after 1am. Mostly cloudy, with a low around 45.
Wednesday
A 20 percent chance of showers and thunderstorms before 1pm. Partly sunny, with a high near 73.
Wednesday Night
A 20 percent chance of showers. Partly cloudy, with a low around 56.
Thursday
A 20 percent chance of showers. Sunny, with a high near 82.
Thursday Night
A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 47.
Friday
A 30 percent chance of showers. Partly sunny, with a high near 58.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Cahokia IL
 38.57°N 90.18°W (Elev. 407 ft)
Last Update:
4:16 am CDT Mar 21, 2026
Forecast Valid:
4am CDT Mar 21, 2026-6pm CDT Mar 27, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation