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.

Partly Cloudy

82°F

28°C

Humidity 74%
Wind Speed SE 6 mph
Barometer 30.04 in
Dewpoint 73°F (23°C)
Visibility 10.00 mi
Heat Index87°F (31°C)
Last update 18 Jul 6:50 pm CDT
Extended Forecast for

2 Miles WSW Alton IL

Extreme Heat Warning July 19, 12:00pm until July 23, 07:00pm
Click here for hazard details and duration
Extreme Heat Warning

  • Tonight

    Tonight: Scattered showers and thunderstorms. Mostly cloudy, with a low around 74. Southeast wind around 6 mph becoming calm in the evening. Chance of precipitation is 30%.

    Low: 74 °F

    Scattered
    T-storms

  • Saturday

    Saturday: A chance of showers, with thunderstorms also possible after 7am. Mostly cloudy, then gradually becoming sunny, with a high near 91. Heat index values as high as 101. Light and variable wind becoming southwest 5 to 7 mph in the morning. Chance of precipitation is 50%.

    High: 91 °F

    Chance
    T-storms

  • Saturday Night

    Saturday Night: A chance of showers and thunderstorms before 1am, then a slight chance of showers. Mostly clear, with a low around 76. Southwest wind 3 to 6 mph. Chance of precipitation is 30%.

    Low: 76 °F

    Chance
    Showers

  • Sunday

    Sunday: A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 95. Heat index values as high as 106. West wind 3 to 6 mph.

    High: 95 °F

    Slight Chance
    T-storms

  • Sunday Night

    Sunday Night: A 30 percent chance of showers and thunderstorms. Partly cloudy, with a low around 76. Southwest wind around 5 mph becoming light and variable in the evening.

    Low: 76 °F

    Chance
    T-storms

  • Monday

    Monday: A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 94.

    High: 94 °F

    Slight Chance
    T-storms

  • Monday Night

    Monday Night: A 20 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 77.

    Low: 77 °F

    Slight Chance
    T-storms

  • Tuesday

    Tuesday: Mostly sunny, with a high near 96.

    High: 96 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 78.

    Low: 78 °F

    Mostly Clear

Detailed Forecast

Tonight
Scattered showers and thunderstorms. Mostly cloudy, with a low around 74. Southeast wind around 6 mph becoming calm in the evening. Chance of precipitation is 30%.
Saturday
A chance of showers, with thunderstorms also possible after 7am. Mostly cloudy, then gradually becoming sunny, with a high near 91. Heat index values as high as 101. Light and variable wind becoming southwest 5 to 7 mph in the morning. Chance of precipitation is 50%.
Saturday Night
A chance of showers and thunderstorms before 1am, then a slight chance of showers. Mostly clear, with a low around 76. Southwest wind 3 to 6 mph. Chance of precipitation is 30%.
Sunday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 95. Heat index values as high as 106. West wind 3 to 6 mph.
Sunday Night
A 30 percent chance of showers and thunderstorms. Partly cloudy, with a low around 76. Southwest wind around 5 mph becoming light and variable in the evening.
Monday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 94.
Monday Night
A 20 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 77.
Tuesday
Mostly sunny, with a high near 96.
Tuesday Night
Mostly clear, with a low around 78.
Wednesday
Sunny and hot, with a high near 99.
Wednesday Night
Mostly clear, with a low around 78.
Thursday
Sunny and hot, with a high near 98.
Thursday Night
Mostly clear, with a low around 77.
Friday
Sunny and hot, with a high near 97.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
2 Miles WSW Alton IL
 38.88°N 90.19°W (Elev. 407 ft)
Last Update:
5:36 pm CDT Jul 18, 2025
Forecast Valid:
7pm CDT Jul 18, 2025-6pm CDT Jul 25, 2025
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

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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