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

52°F

11°C

Humidity 30%
Wind Speed S 17 G 30 mph
Barometer 29.60 in
Dewpoint 21°F (-6°C)
Visibility 10.00 mi
Wind Chill47°F (8°C)
Last update 24 Feb 3:50 pm CST
Extended Forecast for

Alton IL

  • Tonight

    Tonight: Mostly cloudy, with a low around 35. Southwest wind 5 to 10 mph becoming light and variable after midnight.

    Low: 35 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Partly sunny, with a high near 52. Calm wind becoming north around 6 mph.

    High: 52 °F

    Partly Sunny

  • Wednesday Night

    Wednesday Night: A 50 percent chance of rain. Mostly cloudy, with a low around 35. East wind 3 to 6 mph.

    Low: 35 °F

    Chance Rain

  • Thursday

    Thursday: A 20 percent chance of rain before noon. Partly sunny, with a high near 51. East wind around 6 mph becoming northwest in the afternoon.

    High: 51 °F

    Slight Chance
    Rain then
    Mostly Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 34. Light and variable wind.

    Low: 34 °F

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 66.

    High: 66 °F

    Sunny

  • Friday Night

    Friday Night: Mostly clear, with a low around 41.

    Low: 41 °F

    Mostly Clear

  • Saturday

    Saturday: Sunny, with a high near 66.

    High: 66 °F

    Sunny

  • Saturday Night

    Saturday Night: A slight chance of rain before midnight, then a slight chance of rain and snow. Partly cloudy, with a low around 32. Chance of precipitation is 20%.

    Low: 32 °F

    Slight Chance
    Rain then
    Slight Chance
    Rain/Snow

Detailed Forecast

Tonight
Mostly cloudy, with a low around 35. Southwest wind 5 to 10 mph becoming light and variable after midnight.
Wednesday
Partly sunny, with a high near 52. Calm wind becoming north around 6 mph.
Wednesday Night
A 50 percent chance of rain. Mostly cloudy, with a low around 35. East wind 3 to 6 mph.
Thursday
A 20 percent chance of rain before noon. Partly sunny, with a high near 51. East wind around 6 mph becoming northwest in the afternoon.
Thursday Night
Mostly clear, with a low around 34. Light and variable wind.
Friday
Sunny, with a high near 66.
Friday Night
Mostly clear, with a low around 41.
Saturday
Sunny, with a high near 66.
Saturday Night
A slight chance of rain before midnight, then a slight chance of rain and snow. Partly cloudy, with a low around 32. Chance of precipitation is 20%.
Sunday
A chance of rain and snow, mainly after noon. Mostly cloudy, with a high near 46. Chance of precipitation is 30%.
Sunday Night
A chance of rain and snow. Mostly cloudy, with a low around 33. Chance of precipitation is 50%.
Monday
A 30 percent chance of rain. Mostly cloudy, with a high near 49.
Monday Night
A 30 percent chance of rain and thunderstorms. Mostly cloudy, with a low around 34.
Tuesday
A 50 percent chance of rain. Mostly cloudy, with a high near 52.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Alton IL
 38.88°N 90.16°W (Elev. 466 ft)
Last Update:
3:36 pm CST Feb 24, 2026
Forecast Valid:
5pm CST Feb 24, 2026-6pm CST Mar 3, 2026
 
Forecast Discussion
 
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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

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation