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

49°F

9°C

Humidity 93%
Wind Speed S 3 mph
Barometer 30.07 in (1018.1 mb)
Dewpoint 47°F (8°C)
Visibility 10.00 mi
Last update 9 Oct 3:53 am CDT
Extended Forecast for

Mascoutah IL

  • Overnight

    Overnight: Patchy fog. Otherwise, clear, with a low around 50. Calm wind.

    Low: 50 °F

    Patchy Fog

  • Friday

    Friday: Patchy fog before 9am. Otherwise, sunny, with a high near 89. Light southeast wind becoming south 5 to 10 mph in the morning.

    High: 89 °F

    Patchy Fog
    then Sunny

  • Friday Night

    Friday Night: Increasing clouds, with a low around 58. Southeast wind around 6 mph becoming calm in the evening.

    Low: 58 °F

    Increasing
    Clouds

  • Saturday

    Saturday: Cloudy, with a high near 79. Calm wind becoming south 5 to 8 mph in the afternoon.

    High: 79 °F

    Cloudy

  • Saturday Night

    Saturday Night: A 20 percent chance of showers. Mostly cloudy, with a low around 59. East wind 5 to 8 mph.

    Low: 59 °F

    Slight Chance
    Showers

  • Sunday

    Sunday: Mostly sunny, with a high near 81.

    High: 81 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 59.

    Low: 59 °F

    Mostly Clear

  • Columbus Day

    Columbus Day: Sunny, with a high near 92.

    High: 92 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 67.

    Low: 67 °F

    Mostly Clear

Detailed Forecast

Overnight
Patchy fog. Otherwise, clear, with a low around 50. Calm wind.
Friday
Patchy fog before 9am. Otherwise, sunny, with a high near 89. Light southeast wind becoming south 5 to 10 mph in the morning.
Friday Night
Increasing clouds, with a low around 58. Southeast wind around 6 mph becoming calm in the evening.
Saturday
Cloudy, with a high near 79. Calm wind becoming south 5 to 8 mph in the afternoon.
Saturday Night
A 20 percent chance of showers. Mostly cloudy, with a low around 59. East wind 5 to 8 mph.
Sunday
Mostly sunny, with a high near 81.
Sunday Night
Mostly clear, with a low around 59.
Columbus Day
Sunny, with a high near 92.
Monday Night
Mostly clear, with a low around 67.
Tuesday
Sunny, with a high near 90.
Tuesday Night
Mostly clear, with a low around 62.
Wednesday
A 40 percent chance of showers. Mostly sunny, with a high near 84.
Wednesday Night
A 20 percent chance of showers. Partly cloudy, with a low around 64.
Thursday
A 50 percent chance of showers and thunderstorms. Mostly sunny, with a high near 83.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Mascoutah IL
 38.5°N 89.81°W (Elev. 427 ft)
Last Update:
1:25 am CDT Oct 9, 2026
Forecast Valid:
3am CDT Oct 9, 2026-6pm CDT Oct 15, 2026
 
Forecast Discussion
 
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Additional Resources

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Hourly Weather Forecast

National Digital Forecast Database

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High Temperature

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Chance of Precipitation