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

Mattoon / Charleston, Coles County Memorial Airport (KMTO)

Lat: 39.48°NLon: 88.28°WElev: 722ft.

Fair

26°F

-3°C

Humidity 46%
Wind Speed S 14 G 24 mph
Barometer 30.20 in (1023.7 mb)
Dewpoint 8°F (-13°C)
Visibility 10.00 mi
Wind Chill14°F (-10°C)
Last update 20 Jan 9:53 pm CST
Extended Forecast for

Sullivan IL

  • Tonight

    Tonight: Mostly cloudy, with a low around 24. South wind 13 to 15 mph, with gusts as high as 25 mph.

    Low: 24 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Mostly cloudy, then gradually becoming sunny, with a high near 40. West wind 10 to 16 mph, with gusts as high as 26 mph.

    High: 40 °F

    Decreasing
    Clouds

  • Wednesday Night

    Wednesday Night: Partly cloudy, with a low around 19. West northwest wind 8 to 13 mph, with gusts as high as 22 mph.

    Low: 19 °F

    Partly Cloudy

  • Thursday

    Thursday: Partly sunny, with a high near 30. West northwest wind 5 to 8 mph.

    High: 30 °F

    Partly Sunny

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 4. Light northwest wind becoming north northwest 9 to 14 mph in the evening. Winds could gust as high as 21 mph.

    Low: 4 °F

    Mostly Cloudy

  • Friday

    Friday: Partly sunny and cold, with a high near 8. North wind 11 to 14 mph, with gusts as high as 22 mph.

    High: 8 °F

    Cold

  • Friday Night

    Friday Night: Mostly cloudy, with a low around -2. North northeast wind around 10 mph, with gusts as high as 17 mph.

    Low: -2 °F

    Mostly Cloudy

  • Saturday

    Saturday: A 30 percent chance of snow after noon. Mostly cloudy, with a high near 12.

    High: 12 °F

    Cloudy then
    Chance Snow

  • Saturday Night

    Saturday Night: A 30 percent chance of snow before midnight. Mostly cloudy, with a low around 5.

    Low: 5 °F

    Chance Snow
    then Mostly
    Cloudy

Detailed Forecast

Tonight
Mostly cloudy, with a low around 24. South wind 13 to 15 mph, with gusts as high as 25 mph.
Wednesday
Mostly cloudy, then gradually becoming sunny, with a high near 40. West wind 10 to 16 mph, with gusts as high as 26 mph.
Wednesday Night
Partly cloudy, with a low around 19. West northwest wind 8 to 13 mph, with gusts as high as 22 mph.
Thursday
Partly sunny, with a high near 30. West northwest wind 5 to 8 mph.
Thursday Night
Mostly cloudy, with a low around 4. Light northwest wind becoming north northwest 9 to 14 mph in the evening. Winds could gust as high as 21 mph.
Friday
Partly sunny and cold, with a high near 8. North wind 11 to 14 mph, with gusts as high as 22 mph.
Friday Night
Mostly cloudy, with a low around -2. North northeast wind around 10 mph, with gusts as high as 17 mph.
Saturday
A 30 percent chance of snow after noon. Mostly cloudy, with a high near 12.
Saturday Night
A 30 percent chance of snow before midnight. Mostly cloudy, with a low around 5.
Sunday
Partly sunny, with a high near 18.
Sunday Night
Partly cloudy, with a low around 3.
Monday
Mostly sunny, with a high near 19.
Monday Night
Partly cloudy, with a low around 6.
Tuesday
Mostly sunny, with a high near 28.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Sullivan IL
 39.59°N 88.61°W (Elev. 669 ft)
Last Update:
9:36 pm CST Jan 20, 2026
Forecast Valid:
10pm CST Jan 20, 2026-6pm CST Jan 27, 2026
 
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Additional Resources

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation