Thunderstorms and Heavy Rain in the Mid-South; Heat Continues in the Southeast and Southwest

Severe thunderstorms and heavy rain are expected across portions of the mid-Mississippi Valley into the Ohio Valley and portions of Arizona. Dangerous heat persists in the South and Southeast while building into the Southwest. Overnight lows will be so warm that, when combined with oppressive dew points, little-to-no relief from the scorching daytime highs will be available. Read More >

Current conditions at

St. Louis Regional Airport (KALN)

Lat: 38.89°NLon: 90.03°WElev: 518ft.

Partly Cloudy

79°F

26°C

Humidity 79%
Wind Speed W 3 mph
Barometer 29.93 in
Dewpoint 72°F (22°C)
Visibility 10.00 mi
Heat Index82°F (28°C)
Last update 19 Aug 3:50 pm CDT
Extended Forecast for

Grantfork IL

  • This Afternoon

    This Afternoon: A 30 percent chance of showers and thunderstorms.  Mostly cloudy, with a high near 80. Light west wind.

    High: 80 °F

    Chance
    T-storms

  • Tonight

    Tonight: A 30 percent chance of showers and thunderstorms, mainly before 2am.  Patchy fog after 2am.  Otherwise, mostly cloudy, with a low around 69. Light northeast wind.

    Low: 69 °F

    Chance
    T-storms and
    Patchy Fog

  • Thursday

    Thursday: Patchy fog before 9am.  Otherwise, partly sunny, with a high near 82. Calm wind becoming northeast around 5 mph in the afternoon.

    High: 82 °F

    Patchy Fog
    then Mostly
    Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 64. Light north wind.

    Low: 64 °F

    Mostly Clear

  • Friday

    Friday: Sunny, with a high near 84. Light and variable wind.

    High: 84 °F

    Sunny

  • Friday Night

    Friday Night: A 20 percent chance of showers and thunderstorms.  Mostly clear, with a low around 66.

    Low: 66 °F

    Slight Chance
    T-storms

  • Saturday

    Saturday: Sunny, with a high near 84.

    High: 84 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 64.

    Low: 64 °F

    Mostly Clear

  • Sunday

    Sunday: Mostly sunny, with a high near 82.

    High: 82 °F

    Mostly Sunny

Detailed Forecast

This Afternoon
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 80. Light west wind.
Tonight
A 30 percent chance of showers and thunderstorms, mainly before 2am. Patchy fog after 2am. Otherwise, mostly cloudy, with a low around 69. Light northeast wind.
Thursday
Patchy fog before 9am. Otherwise, partly sunny, with a high near 82. Calm wind becoming northeast around 5 mph in the afternoon.
Thursday Night
Mostly clear, with a low around 64. Light north wind.
Friday
Sunny, with a high near 84. Light and variable wind.
Friday Night
A 20 percent chance of showers and thunderstorms. Mostly clear, with a low around 66.
Saturday
Sunny, with a high near 84.
Saturday Night
Mostly clear, with a low around 64.
Sunday
Mostly sunny, with a high near 82.
Sunday Night
A 20 percent chance of showers. Mostly cloudy, with a low around 63.
Monday
Mostly sunny, with a high near 82.
Monday Night
A 20 percent chance of showers and thunderstorms. Partly cloudy, with a low around 65.
Tuesday
Mostly sunny, with a high near 85.
Tuesday Night
Partly cloudy, with a low around 67.
Wednesday
Mostly sunny, with a high near 87.
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ABOUT THIS FORECAST

 
Point Forecast:
Grantfork IL
 38.82°N 89.65°W (Elev. 577 ft)
4:16 pm CDT Aug 19, 2026
4pm CDT Aug 19, 2026-6pm CDT Aug 26, 2026
 
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Additional Resources

Radar & Satellite Image

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Hourly Weather Forecast

National Digital Forecast Database