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

48°F

9°C

Humidity 82%
Wind Speed Vrbl 3 mph
Barometer 30.01 in
Dewpoint 43°F (6°C)
Visibility 10.00 mi
Last update 15 Feb 6:50 pm CST
Extended Forecast for

Alton ILSimilar City Names

  • Tonight

    Tonight: Patchy dense fog after 1am. Otherwise, partly cloudy, with a low around 36. Light and variable wind.

    Low: 36 °F

    Mostly Clear
    then Patchy
    Dense Fog

  • Washington's Birthday

    Washington's Birthday: Patchy dense fog before 8am. Otherwise, partly sunny, with a high near 64. Light south wind increasing to 5 to 10 mph in the morning.

    High: 64 °F

    Patchy Dense
    Fog then
    Mostly Sunny

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 43. South wind 6 to 8 mph.

    Low: 43 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Mostly cloudy, with a high near 64. South wind 6 to 16 mph, with gusts as high as 26 mph.

    High: 64 °F

    Mostly Cloudy

  • Tuesday Night

    Tuesday Night: A 20 percent chance of showers after midnight. Mostly cloudy, with a low around 56. South wind 15 to 18 mph, with gusts as high as 28 mph.

    Low: 56 °F

    Mostly Cloudy
    then Slight
    Chance
    Showers

  • Wednesday

    Wednesday: Sunny, with a high near 70.

    High: 70 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 46.

    Low: 46 °F

    Partly Cloudy

  • Thursday

    Thursday: A slight chance of showers, with thunderstorms also possible after noon. Sunny, with a high near 72. Chance of precipitation is 20%.

    High: 72 °F

    Slight Chance
    Showers then
    Slight Chance
    T-storms

  • Thursday Night

    Thursday Night: A 20 percent chance of showers and thunderstorms before midnight. Mostly clear, with a low around 38.

    Low: 38 °F

    Slight Chance
    T-storms then
    Mostly Clear

Detailed Forecast

Tonight
Patchy dense fog after 1am. Otherwise, partly cloudy, with a low around 36. Light and variable wind.
Washington's Birthday
Patchy dense fog before 8am. Otherwise, partly sunny, with a high near 64. Light south wind increasing to 5 to 10 mph in the morning.
Monday Night
Mostly cloudy, with a low around 43. South wind 6 to 8 mph.
Tuesday
Mostly cloudy, with a high near 64. South wind 6 to 16 mph, with gusts as high as 26 mph.
Tuesday Night
A 20 percent chance of showers after midnight. Mostly cloudy, with a low around 56. South wind 15 to 18 mph, with gusts as high as 28 mph.
Wednesday
Sunny, with a high near 70.
Wednesday Night
Partly cloudy, with a low around 46.
Thursday
A slight chance of showers, with thunderstorms also possible after noon. Sunny, with a high near 72. Chance of precipitation is 20%.
Thursday Night
A 20 percent chance of showers and thunderstorms before midnight. Mostly clear, with a low around 38.
Friday
A 20 percent chance of rain after noon. Mostly sunny, with a high near 51.
Friday Night
A 30 percent chance of rain. Mostly cloudy, with a low around 31.
Saturday
A 20 percent chance of rain. Mostly sunny, with a high near 48.
Saturday Night
A 20 percent chance of rain. Mostly clear, with a low around 28.
Sunday
Mostly sunny, with a high near 45.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Alton ILSimilar City Names
 38.91°N 90.16°W (Elev. 505 ft)
Last Update:
6:36 pm CST Feb 15, 2026
Forecast Valid:
7pm CST Feb 15, 2026-6pm CST Feb 22, 2026
 
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