Current conditions at
St. Louis Regional Airport (KALN)
Lat: 38.89°NLon: 90.03°WElev: 518ft.
Fair
51°F
11°C
| Humidity | 75% |
| Wind Speed | Calm |
| Barometer | 29.99 in |
| Dewpoint | 44°F (7°C) |
| Visibility | 10.00 mi |
| Last update | 20 Mar 12:15 am CDT |
Extended Forecast for
Williamson IL
Overnight
Low: 48 °F
Partly Cloudy
Friday
High: 81 °F
Sunny
Friday Night
Low: 48 °F
Partly Cloudy
Saturday
High: 77 °F
Sunny
Saturday Night
Low: 57 °F
Clear
Sunday
High: 82 °F
Mostly Sunny
Sunday Night
Low: 39 °F
Partly Cloudy
Monday
High: 55 °F
Mostly Sunny
Monday Night
Low: 37 °F
Partly Cloudy
Detailed Forecast
Overnight
Partly cloudy, with a low around 48. Southwest wind around 7 mph.
Friday
Sunny, with a high near 81. West wind 7 to 11 mph.
Friday Night
Partly cloudy, with a low around 48. Northwest wind around 6 mph becoming light and variable after midnight.
Saturday
Sunny, with a high near 77. Calm wind becoming southwest around 6 mph in the afternoon.
Saturday Night
Clear, with a low around 57. South wind 5 to 9 mph.
Sunday
Mostly sunny, with a high near 82.
Sunday Night
Partly cloudy, with a low around 39.
Monday
Mostly sunny, with a high near 55.
Monday Night
Partly cloudy, with a low around 37.
Tuesday
Partly sunny, with a high near 58.
Tuesday Night
Mostly cloudy, with a low around 41.
Wednesday
Partly sunny, with a high near 67.
Wednesday Night
Partly cloudy, with a low around 52.
Thursday
A 20 percent chance of rain. Sunny, with a high near 74. Breezy.
Additional Forecasts and Information
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Forecast AreaABOUT THIS FORECAST
Point Forecast:
Williamson IL
38.98°N 89.76°W (Elev. 597 ft)
38.98°N 89.76°W (Elev. 597 ft)
10:21 pm CDT Mar 19, 2026
12am CDT Mar 20, 2026-6pm CDT Mar 26, 2026
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