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

St. Louis Regional Airport (KALN)

Lat: 38.89°NLon: 90.03°WElev: 518ft.

Fair and Breezy

73°F

23°C

Humidity 44%
Wind Speed S 23 G 32 mph
Barometer 29.67 in
Dewpoint 50°F (10°C)
Visibility 10.00 mi
Last update 13 Apr 2:50 pm CDT
Extended Forecast for

Alton ILSimilar City Names

  • Tonight

    Tonight: Partly cloudy, with a low around 58. South wind 9 to 16 mph becoming west after midnight.

    Low: 58 °F

    Partly Cloudy

  • Monday

    Monday: A slight chance of showers or sprinkles before 10am, then a slight chance of sprinkles between 10am and 11am. Mostly cloudy, with a high near 66. Northwest wind 11 to 16 mph, with gusts as high as 24 mph. Chance of precipitation is 20%.

    High: 66 °F

    Slight Chance
    Showers then
    Mostly Cloudy

  • Monday Night

    Monday Night: Mostly cloudy during the early evening, then gradual clearing, with a low around 44. West wind 11 to 15 mph, with gusts as high as 26 mph.

    Low: 44 °F

    Gradual
    Clearing

  • Tuesday

    Tuesday: Sunny, with a high near 61. Northwest wind 14 to 17 mph, with gusts as high as 28 mph.

    High: 61 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Clear, with a low around 39. Northwest wind 5 to 10 mph becoming light after midnight.

    Low: 39 °F

    Clear

  • Wednesday

    Wednesday: Mostly sunny, with a high near 66.

    High: 66 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: A 40 percent chance of showers, mainly after 1am. Mostly cloudy, with a low around 51.

    Low: 51 °F

    Chance
    Showers

  • Thursday

    Thursday: A 50 percent chance of showers and thunderstorms, mainly before 1pm. Partly sunny, with a high near 70.

    High: 70 °F

    Chance
    Showers

  • Thursday Night

    Thursday Night: A 20 percent chance of showers after 1am. Partly cloudy, with a low around 60.

    Low: 60 °F

    Partly Cloudy
    then Slight
    Chance
    Showers

Detailed Forecast

Tonight
Partly cloudy, with a low around 58. South wind 9 to 16 mph becoming west after midnight.
Monday
A slight chance of showers or sprinkles before 10am, then a slight chance of sprinkles between 10am and 11am. Mostly cloudy, with a high near 66. Northwest wind 11 to 16 mph, with gusts as high as 24 mph. Chance of precipitation is 20%.
Monday Night
Mostly cloudy during the early evening, then gradual clearing, with a low around 44. West wind 11 to 15 mph, with gusts as high as 26 mph.
Tuesday
Sunny, with a high near 61. Northwest wind 14 to 17 mph, with gusts as high as 28 mph.
Tuesday Night
Clear, with a low around 39. Northwest wind 5 to 10 mph becoming light after midnight.
Wednesday
Mostly sunny, with a high near 66.
Wednesday Night
A 40 percent chance of showers, mainly after 1am. Mostly cloudy, with a low around 51.
Thursday
A 50 percent chance of showers and thunderstorms, mainly before 1pm. Partly sunny, with a high near 70.
Thursday Night
A 20 percent chance of showers after 1am. Partly cloudy, with a low around 60.
Friday
A chance of showers, with thunderstorms also possible after 1pm. Partly sunny, with a high near 83. Chance of precipitation is 30%.
Friday Night
A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 56.
Saturday
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 69.
Saturday Night
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 51.
Sunday
A 40 percent chance of showers and thunderstorms. Partly sunny, with a high near 69.
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ABOUT THIS FORECAST

 
Point Forecast:
Alton ILSimilar City Names
 38.91°N 90.16°W (Elev. 505 ft)
Last Update:
1:51 pm CDT Apr 13, 2025
Forecast Valid:
3pm CDT Apr 13, 2025-6pm CDT Apr 20, 2025
 
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Additional Resources

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High Temperature

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Chance of Precipitation