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

Hazardous Weather Conditions

Current conditions at

St. Louis Regional Airport (KALN)

Lat: 38.89°NLon: 90.03°WElev: 518ft.

Fair and Breezy

46°F

8°C

Humidity 34%
Wind Speed S 24 G 33 mph
Barometer 29.64 in
Dewpoint 19°F (-7°C)
Visibility 10.00 mi
Wind Chill38°F (3°C)
Last update 24 Feb 1:50 pm CST
Extended Forecast for

Williamson IL

  • This Afternoon

    This Afternoon: Mostly cloudy, with a high near 51. Breezy, with a south wind 16 to 22 mph, with gusts as high as 32 mph.

    High: 51 °F

    Mostly Cloudy
    and Breezy

  • Tonight

    Tonight: Mostly cloudy, with a low around 32. Southwest wind 9 to 14 mph becoming light and variable after midnight. Winds could gust as high as 21 mph.

    Low: 32 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Partly sunny, with a high near 49. Calm wind becoming north around 5 mph.

    High: 49 °F

    Partly Sunny

  • Wednesday Night

    Wednesday Night: A 50 percent chance of rain. Mostly cloudy, with a low around 33. Calm wind becoming east 5 to 7 mph in the evening.

    Low: 33 °F

    Chance Rain

  • Thursday

    Thursday: A 20 percent chance of rain before noon. Partly sunny, with a high near 49. East wind 5 to 7 mph becoming north in the afternoon.

    High: 49 °F

    Slight Chance
    Rain then
    Partly Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 32.

    Low: 32 °F

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 63.

    High: 63 °F

    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 39.

    Low: 39 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 63.

    High: 63 °F

    Sunny

Detailed Forecast

This Afternoon
Mostly cloudy, with a high near 51. Breezy, with a south wind 16 to 22 mph, with gusts as high as 32 mph.
Tonight
Mostly cloudy, with a low around 32. Southwest wind 9 to 14 mph becoming light and variable after midnight. Winds could gust as high as 21 mph.
Wednesday
Partly sunny, with a high near 49. Calm wind becoming north around 5 mph.
Wednesday Night
A 50 percent chance of rain. Mostly cloudy, with a low around 33. Calm wind becoming east 5 to 7 mph in the evening.
Thursday
A 20 percent chance of rain before noon. Partly sunny, with a high near 49. East wind 5 to 7 mph becoming north in the afternoon.
Thursday Night
Mostly clear, with a low around 32.
Friday
Sunny, with a high near 63.
Friday Night
Mostly clear, with a low around 39.
Saturday
Sunny, with a high near 63.
Saturday Night
A slight chance of rain and snow. Partly cloudy, with a low around 31. Chance of precipitation is 20%.
Sunday
A chance of rain and snow. Mostly cloudy, with a high near 44. Chance of precipitation is 30%.
Sunday Night
A chance of rain and snow. Mostly cloudy, with a low around 31. Chance of precipitation is 50%.
Monday
A 30 percent chance of rain. Mostly cloudy, with a high near 47.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Williamson IL
 38.98°N 89.76°W (Elev. 597 ft)
Last Update:
2:36 pm CST Feb 24, 2026
Forecast Valid:
2pm CST Feb 24, 2026-6pm CST Mar 2, 2026
 
Forecast Discussion
 
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Additional Resources

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Hourly Weather Forecast

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation