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

Southern Illinois Airport (KMDH)

Lat: 37.78°NLon: 89.25°WElev: 400ft.

Partly Cloudy

30°F

-1°C

Humidity 51%
Wind Speed NW 14 G 29 mph
Barometer 30.38 in (1029.2 mb)
Dewpoint 14°F (-10°C)
Visibility 10.00 mi
Wind Chill19°F (-7°C)
Last update 11 Jan 5:52 am CST
Extended Forecast for

Alto Pass IL

  • Today

    Today: Sunny, with a high near 38. Northwest wind 5 to 14 mph, with gusts as high as 30 mph.

    High: 38 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 26. Calm wind becoming south southwest around 6 mph after midnight.

    Low: 26 °F

    Mostly Clear

  • Monday

    Monday: Sunny, with a high near 49. South southwest wind 7 to 10 mph, with gusts as high as 18 mph.

    High: 49 °F

    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 35. South southwest wind 7 to 9 mph.

    Low: 35 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 57. Southwest wind 9 to 14 mph, with gusts as high as 24 mph.

    High: 57 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: A 20 percent chance of showers after midnight. Mostly cloudy, with a low around 40. West wind 6 to 10 mph.

    Low: 40 °F

    Mostly Cloudy
    then Slight
    Chance
    Showers

  • Wednesday

    Wednesday: A 20 percent chance of showers. Partly sunny, with a high near 45. North northwest wind 7 to 14 mph, with gusts as high as 24 mph.

    High: 45 °F

    Slight Chance
    Showers

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 19. North northwest wind 9 to 14 mph, with gusts as high as 21 mph.

    Low: 19 °F

    Partly Cloudy

  • Thursday

    Thursday: Mostly sunny, with a high near 36. North northwest wind 5 to 8 mph becoming southwest in the afternoon.

    High: 36 °F

    Mostly Sunny

Detailed Forecast

Today
Sunny, with a high near 38. Northwest wind 5 to 14 mph, with gusts as high as 30 mph.
Tonight
Mostly clear, with a low around 26. Calm wind becoming south southwest around 6 mph after midnight.
Monday
Sunny, with a high near 49. South southwest wind 7 to 10 mph, with gusts as high as 18 mph.
Monday Night
Mostly clear, with a low around 35. South southwest wind 7 to 9 mph.
Tuesday
Mostly sunny, with a high near 57. Southwest wind 9 to 14 mph, with gusts as high as 24 mph.
Tuesday Night
A 20 percent chance of showers after midnight. Mostly cloudy, with a low around 40. West wind 6 to 10 mph.
Wednesday
A 20 percent chance of showers. Partly sunny, with a high near 45. North northwest wind 7 to 14 mph, with gusts as high as 24 mph.
Wednesday Night
Partly cloudy, with a low around 19. North northwest wind 9 to 14 mph, with gusts as high as 21 mph.
Thursday
Mostly sunny, with a high near 36. North northwest wind 5 to 8 mph becoming southwest in the afternoon.
Thursday Night
Partly cloudy, with a low around 27. South wind 6 to 9 mph.
Friday
Partly sunny, with a high near 43. West wind 8 to 11 mph, with gusts as high as 21 mph.
Friday Night
Mostly cloudy, with a low around 25. West wind 6 to 8 mph.
Saturday
Partly sunny, with a high near 34. West wind 8 to 10 mph, with gusts as high as 18 mph.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Alto Pass IL
 37.57°N 89.32°W
Last Update:
5:26 am CST Jan 11, 2026
Forecast Valid:
6am CST Jan 11, 2026-6pm CST Jan 17, 2026
 
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Additional Resources

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