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.

Fog/Mist

52°F

11°C

Humidity 97%
Wind Speed Calm
Barometer 29.81 in
Dewpoint 51°F (11°C)
Visibility 3.00 mi
Last update 25 Nov 5:55 am CST
Extended Forecast for

Alton IL

  • Today

    Today: Patchy drizzle before 10am. Patchy fog between 8am and 9am. Otherwise, cloudy, with a high near 57. Light southwest wind becoming west 5 to 10 mph in the morning.

    High: 57 °F

    Patchy
    Drizzle and
    Patchy Fog
    then Cloudy

  • Tonight

    Tonight: Isolated showers between 7pm and 9pm. Cloudy during the early evening, then gradual clearing, with a low around 35. Breezy, with a west wind 9 to 14 mph increasing to 15 to 20 mph after midnight. Winds could gust as high as 34 mph. Chance of precipitation is 20%.

    Low: 35 °F

    Isolated
    Showers then
    Partly Cloudy
    and Breezy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 45. Breezy, with a west wind 13 to 21 mph, with gusts as high as 34 mph.

    High: 45 °F

    Mostly Sunny
    and Breezy

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 27. West wind 7 to 10 mph.

    Low: 27 °F

    Partly Cloudy

  • Thanksgiving Day

    Thanksgiving Day: Sunny, with a high near 41. Northwest wind 7 to 11 mph, with gusts as high as 20 mph.

    High: 41 °F

    Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 22.

    Low: 22 °F

    Mostly Clear

  • Friday

    Friday: Mostly sunny, with a high near 38.

    High: 38 °F

    Mostly Sunny

  • Friday Night

    Friday Night: A chance of snow before midnight, then rain and snow likely. Cloudy, with a low around 30. Chance of precipitation is 60%.

    Low: 30 °F

    Chance Snow
    then
    Rain/Snow
    Likely

  • Saturday

    Saturday: Rain and snow. High near 39. Chance of precipitation is 80%.

    High: 39 °F

    Rain/Snow

Detailed Forecast

Today
Patchy drizzle before 10am. Patchy fog between 8am and 9am. Otherwise, cloudy, with a high near 57. Light southwest wind becoming west 5 to 10 mph in the morning.
Tonight
Isolated showers between 7pm and 9pm. Cloudy during the early evening, then gradual clearing, with a low around 35. Breezy, with a west wind 9 to 14 mph increasing to 15 to 20 mph after midnight. Winds could gust as high as 34 mph. Chance of precipitation is 20%.
Wednesday
Mostly sunny, with a high near 45. Breezy, with a west wind 13 to 21 mph, with gusts as high as 34 mph.
Wednesday Night
Partly cloudy, with a low around 27. West wind 7 to 10 mph.
Thanksgiving Day
Sunny, with a high near 41. Northwest wind 7 to 11 mph, with gusts as high as 20 mph.
Thursday Night
Mostly clear, with a low around 22.
Friday
Mostly sunny, with a high near 38.
Friday Night
A chance of snow before midnight, then rain and snow likely. Cloudy, with a low around 30. Chance of precipitation is 60%.
Saturday
Rain and snow. High near 39. Chance of precipitation is 80%.
Saturday Night
Rain likely, mainly before midnight. Cloudy, with a low around 29. Chance of precipitation is 60%.
Sunday
A 40 percent chance of rain. Mostly cloudy, with a high near 39.
Sunday Night
A chance of rain and snow. Mostly cloudy, with a low around 28. Chance of precipitation is 40%.
Monday
A 40 percent chance of rain. Mostly cloudy, with a high near 38.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Alton IL
 38.91°N 90.16°W (Elev. 505 ft)
Last Update:
4:31 am CST Nov 25, 2025
Forecast Valid:
6am CST Nov 25, 2025-6pm CST Dec 1, 2025
 
Forecast Discussion
 
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Additional Resources

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation