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Hazardous Weather Conditions

Current conditions at

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Overcast

61°F

16°C

Humidity 83%
Wind Speed N 9 mph
Barometer 30.17 in
Dewpoint 55°F (13°C)
Visibility 10.00 mi
Last update 20 May 10:57 am CDT
Extended Forecast for

Alto Pass IL

  • Today

    Today: A 30 percent chance of showers, mainly before 1pm. Cloudy, with a high near 65. North wind around 9 mph, with gusts as high as 18 mph.

    High: 65 °F

    Chance
    Showers

  • Tonight

    Tonight: Mostly cloudy, with a low around 55. North northeast wind 5 to 9 mph.

    Low: 55 °F

    Mostly Cloudy

  • Thursday

    Thursday: Mostly cloudy, with a high near 72. Northeast wind 6 to 8 mph.

    High: 72 °F

    Mostly Cloudy

  • Thursday Night

    Thursday Night: Showers likely and possibly a thunderstorm, mainly after 4am. Mostly cloudy, with a low around 59. East northeast wind 6 to 8 mph. Chance of precipitation is 70%.

    Low: 59 °F

    Mostly Cloudy
    then Showers
    Likely

  • Friday

    Friday: Showers and possibly a thunderstorm. High near 74. East wind 6 to 8 mph becoming south in the afternoon. Chance of precipitation is 90%.

    High: 74 °F

    Showers

  • Friday Night

    Friday Night: A chance of showers and thunderstorms before 1am, then a slight chance of showers. Mostly cloudy, with a low around 62. Southwest wind 3 to 7 mph. Chance of precipitation is 50%.

    Low: 62 °F

    Chance
    T-storms

  • Saturday

    Saturday: A 30 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 81. Southwest wind 3 to 5 mph.

    High: 81 °F

    Partly Sunny
    then Chance
    T-storms

  • Saturday Night

    Saturday Night: A chance of showers and thunderstorms. Mostly cloudy, with a low around 64. Light south southeast wind.

    Low: 64 °F

    Chance
    T-storms

  • Sunday

    Sunday: Showers likely and possibly a thunderstorm. Mostly cloudy, with a high near 80. Calm wind becoming south around 5 mph.

    High: 80 °F

    Showers
    Likely

Detailed Forecast

Today
A 30 percent chance of showers, mainly before 1pm. Cloudy, with a high near 65. North wind around 9 mph, with gusts as high as 18 mph.
Tonight
Mostly cloudy, with a low around 55. North northeast wind 5 to 9 mph.
Thursday
Mostly cloudy, with a high near 72. Northeast wind 6 to 8 mph.
Thursday Night
Showers likely and possibly a thunderstorm, mainly after 4am. Mostly cloudy, with a low around 59. East northeast wind 6 to 8 mph. Chance of precipitation is 70%.
Friday
Showers and possibly a thunderstorm. High near 74. East wind 6 to 8 mph becoming south in the afternoon. Chance of precipitation is 90%.
Friday Night
A chance of showers and thunderstorms before 1am, then a slight chance of showers. Mostly cloudy, with a low around 62. Southwest wind 3 to 7 mph. Chance of precipitation is 50%.
Saturday
A 30 percent chance of showers and thunderstorms after 1pm. Partly sunny, with a high near 81. Southwest wind 3 to 5 mph.
Saturday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 64. Light south southeast wind.
Sunday
Showers likely and possibly a thunderstorm. Mostly cloudy, with a high near 80. Calm wind becoming south around 5 mph.
Sunday Night
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 64. Calm wind.
Memorial Day
Showers likely and possibly a thunderstorm. Mostly cloudy, with a high near 81. Southeast wind 3 to 6 mph.
Monday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 65. South southeast wind around 5 mph becoming calm in the evening.
Tuesday
A chance of showers and thunderstorms. Partly sunny, with a high near 83. South southeast wind 3 to 7 mph.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Alto Pass IL
 37.57°N 89.32°W
Last Update:
10:16 am CDT May 20, 2026
Forecast Valid:
11am CDT May 20, 2026-6pm CDT May 26, 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