Areas of Dangerous Heat and Severe Thunderstorms

Dangerous heat will persist across the Southwest U.S. through Friday with daytime highs of 110-115°F. Heat across the southern Plains will briefly ease to near-normal by late week before returning over much of the Plains into next week. Scattered strong to severe thunderstorms are possible across parts of the Northeast U.S. on Thursday. Damaging wind, hail, and a tornado or two are possible. Read More >

Current conditions at

St. Louis Regional Airport (KALN)

Lat: 38.89°NLon: 90.03°WElev: 518ft.

Fair

67°F

19°C

Humidity 92%
Wind Speed Calm
Barometer 29.99 in
Dewpoint 65°F (18°C)
Visibility 10.00 mi
Last update 26 Aug 11:55 pm CDT
Extended Forecast for

Williamson IL

  • Overnight

    Overnight: Clear, with a low around 65. Calm wind.

    Low: 65 °F

    Clear

  • Thursday

    Thursday: Sunny, with a high near 86. Calm wind becoming north 5 to 8 mph in the morning.

    High: 86 °F

    Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 61. North wind 5 to 7 mph becoming calm  in the evening.

    Low: 61 °F

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 85. Calm wind becoming northeast around 5 mph in the afternoon.

    High: 85 °F

    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 60. Northeast wind around 5 mph becoming calm  in the evening.

    Low: 60 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 87.

    High: 87 °F

    Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 65.

    Low: 65 °F

    Partly Cloudy

  • Sunday

    Sunday: Sunny, with a high near 93.

    High: 93 °F

    Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 71.

    Low: 71 °F

    Mostly Clear

Detailed Forecast

Overnight
Clear, with a low around 65. Calm wind.
Thursday
Sunny, with a high near 86. Calm wind becoming north 5 to 8 mph in the morning.
Thursday Night
Mostly clear, with a low around 61. North wind 5 to 7 mph becoming calm in the evening.
Friday
Sunny, with a high near 85. Calm wind becoming northeast around 5 mph in the afternoon.
Friday Night
Mostly clear, with a low around 60. Northeast wind around 5 mph becoming calm in the evening.
Saturday
Sunny, with a high near 87.
Saturday Night
Partly cloudy, with a low around 65.
Sunday
Sunny, with a high near 93.
Sunday Night
Mostly clear, with a low around 71.
Monday
Sunny, with a high near 96.
Monday Night
Mostly clear, with a low around 74.
Tuesday
Sunny, with a high near 96.
Tuesday Night
Mostly clear, with a low around 74.
Wednesday
Sunny, with a high near 96.
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ABOUT THIS FORECAST

 
Point Forecast:
Williamson IL
 38.98°N 89.76°W (Elev. 597 ft)
12:01 am CDT Aug 27, 2026
12am CDT Aug 27, 2026-6pm CDT Sep 2, 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