Showers and Storms in the East; Dangerously Hot and Dry in the West

A frontal boundary will bring scattered showers and storms to portions of the Central and Eastern U.S. through the end of the week. Meanwhile, dangerous heat will intensify across the Intermountain West and expand into the Central U.S. by early next week. Elevated wildfire conditions will develop across portions of the Northern/Central Plains and air quality issues will persist in the Northwest. Read More >

Current conditions at

St. Louis Regional Airport (KALN)

Lat: 38.89°NLon: 90.03°WElev: 518ft.

Fair

79°F

26°C

Humidity 79%
Wind Speed E 6 mph
Barometer 30.01 in
Dewpoint 72°F (22°C)
Visibility 10.00 mi
Heat Index82°F (28°C)
Last update 5 Aug 6:45 pm CDT
Extended Forecast for

Alton IL

Flood Watch August 5, 10:00pm until August 6, 10:00am
Click here for hazard details and duration
Flood Watch
  • Tonight

    Tonight: Showers and thunderstorms, mainly after 4am. Some of the storms could produce heavy rainfall.  Low around 72. East wind around 5 mph becoming light and variable  after midnight.  Chance of precipitation is 80%.

    Low: 72 °F

    Chance
    T-storms then
    Heavy Rain

  • Thursday

    Thursday: Showers and thunderstorms, mainly before 1pm. Some of the storms could produce heavy rainfall.  High near 84. Southwest wind 3 to 6 mph.  Chance of precipitation is 80%.

    High: 84 °F

    Heavy Rain
    then Chance
    T-storms

  • Thursday Night

    Thursday Night: A 50 percent chance of showers and thunderstorms, mainly after 10pm.  Mostly cloudy, with a low around 71. Light southeast wind.

    Low: 71 °F

    Chance
    T-storms

  • Friday

    Friday: A 50 percent chance of showers and thunderstorms.  Partly sunny, with a high near 87. South wind 5 to 7 mph becoming southwest in the afternoon.

    High: 87 °F

    Chance
    T-storms

  • Friday Night

    Friday Night: A 40 percent chance of showers and thunderstorms.  Partly cloudy, with a low around 72. Southwest wind 3 to 6 mph.

    Low: 72 °F

    Chance
    T-storms

  • Saturday

    Saturday: Mostly sunny, with a high near 90.

    High: 90 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 73.

    Low: 73 °F

    Mostly Clear

  • Sunday

    Sunday: Mostly sunny, with a high near 93.

    High: 93 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Mostly clear, with a low around 76.

    Low: 76 °F

    Mostly Clear

Detailed Forecast

Tonight
Showers and thunderstorms, mainly after 4am. Some of the storms could produce heavy rainfall. Low around 72. East wind around 5 mph becoming light and variable after midnight. Chance of precipitation is 80%.
Thursday
Showers and thunderstorms, mainly before 1pm. Some of the storms could produce heavy rainfall. High near 84. Southwest wind 3 to 6 mph. Chance of precipitation is 80%.
Thursday Night
A 50 percent chance of showers and thunderstorms, mainly after 10pm. Mostly cloudy, with a low around 71. Light southeast wind.
Friday
A 50 percent chance of showers and thunderstorms. Partly sunny, with a high near 87. South wind 5 to 7 mph becoming southwest in the afternoon.
Friday Night
A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 72. Southwest wind 3 to 6 mph.
Saturday
Mostly sunny, with a high near 90.
Saturday Night
Mostly clear, with a low around 73.
Sunday
Mostly sunny, with a high near 93.
Sunday Night
Mostly clear, with a low around 76.
Monday
Mostly sunny, with a high near 94.
Monday Night
Partly cloudy, with a low around 76.
Tuesday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 93.
Tuesday Night
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 74.
Wednesday
A 30 percent chance of showers and thunderstorms. Partly sunny, with a high near 89.
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ABOUT THIS FORECAST

 
Point Forecast:
Alton IL
 38.88°N 90.16°W (Elev. 466 ft)
7:31 pm CDT Aug 5, 2026
7pm CDT Aug 5, 2026-6pm CDT Aug 12, 2026
 
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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