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

Fire Weather Concerns and Severe Weather

Dry and breezy conditions will bring elevated to critical fire weather conditions across portions of the northern and central High Plains through this weekend, where fuels remain largely receptive. Severe thunderstorms and heavy rainfall are possible from the Plains into the Upper Midwest, as well as in the Ohio Valley and portions of the Mid-Atlantic through this weekend. Read More >

Current conditions at

St. Louis Regional Airport (KALN)

Lat: 38.89°NLon: 90.03°WElev: 518ft.

Fair

75°F

24°C

Humidity 76%
Wind Speed Calm
Barometer 29.97 in
Dewpoint 67°F (19°C)
Visibility 10.00 mi
Last update 12 Sep 10:35 pm CDT
Extended Forecast for

Alton IL

  • Tonight

    Tonight: Partly cloudy, with a low around 69. Light north wind.

    Low: 69 °F

    Partly Cloudy

  • Sunday

    Sunday: Partly sunny, with a high near 87. Light north wind increasing to 5 to 9 mph in the afternoon.

    High: 87 °F

    Partly Sunny

  • Sunday Night

    Sunday Night: Mostly cloudy, with a low around 64. Northeast wind 6 to 9 mph.

    Low: 64 °F

    Mostly Cloudy

  • Monday

    Monday: Mostly cloudy, then gradually becoming sunny, with a high near 87. East wind 10 to 13 mph.

    High: 87 °F

    Decreasing
    Clouds

  • Monday Night

    Monday Night: Mostly clear, with a low around 71. Southeast wind 10 to 13 mph.

    Low: 71 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny and hot, with a high near 97.

    High: 97 °F

    Hot

  • Tuesday Night

    Tuesday Night: A 20 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 72.

    Low: 72 °F

    Slight Chance
    T-storms

  • Wednesday

    Wednesday: Mostly sunny, with a high near 96.

    High: 96 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: A 20 percent chance of showers after 1am. Partly cloudy, with a low around 73.

    Low: 73 °F

    Partly Cloudy
    then Slight
    Chance
    Showers

Detailed Forecast

Tonight
Partly cloudy, with a low around 69. Light north wind.
Sunday
Partly sunny, with a high near 87. Light north wind increasing to 5 to 9 mph in the afternoon.
Sunday Night
Mostly cloudy, with a low around 64. Northeast wind 6 to 9 mph.
Monday
Mostly cloudy, then gradually becoming sunny, with a high near 87. East wind 10 to 13 mph.
Monday Night
Mostly clear, with a low around 71. Southeast wind 10 to 13 mph.
Tuesday
Sunny and hot, with a high near 97.
Tuesday Night
A 20 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 72.
Wednesday
Mostly sunny, with a high near 96.
Wednesday Night
A 20 percent chance of showers after 1am. Partly cloudy, with a low around 73.
Thursday
A chance of showers, with thunderstorms also possible after 1pm. Mostly sunny, with a high near 91. Chance of precipitation is 30%.
Thursday Night
A 30 percent chance of showers and thunderstorms. Partly cloudy, with a low around 67.
Friday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 88.
Friday Night
A 20 percent chance of showers. Partly cloudy, with a low around 64.
Saturday
A 30 percent chance of showers. Mostly sunny, with a high near 84.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Alton IL
 38.91°N 90.16°W (Elev. 505 ft)
Last Update:
10:41 pm CDT Sep 12, 2026
Forecast Valid:
10pm CDT Sep 12, 2026-6pm CDT Sep 19, 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