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

46°F

8°C

Humidity 77%
Wind Speed S 8 mph
Barometer 29.99 in (1015.7 mb)
Dewpoint 39°F (4°C)
Visibility 10.00 mi
Wind Chill42°F (6°C)
Last update 17 Feb 12:53 am CST
Extended Forecast for

Sullivan IL

  • Overnight

    Overnight: Patchy fog after 4am. Otherwise, mostly cloudy, with a low around 39. South wind around 7 mph, with gusts as high as 16 mph.

    Low: 39 °F

    Patchy Fog

  • Tuesday

    Tuesday: Patchy fog before 10am. Otherwise, mostly cloudy, with a high near 59. South wind 8 to 16 mph, with gusts as high as 29 mph.

    High: 59 °F

    Patchy Fog
    then Cloudy

  • Tuesday Night

    Tuesday Night: A 40 percent chance of rain after midnight. Cloudy, then gradually becoming partly cloudy, with a low around 52. Breezy, with a south wind 16 to 21 mph, with gusts as high as 32 mph.

    Low: 52 °F

    Breezy.
    Cloudy then
    Chance Rain

  • Wednesday

    Wednesday: Sunny, with a high near 68. West southwest wind 9 to 18 mph, with gusts as high as 30 mph.

    High: 68 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Increasing clouds, with a low around 45. Southwest wind around 7 mph becoming south southeast after midnight.

    Low: 45 °F

    Increasing
    Clouds

  • Thursday

    Thursday: Rain likely after noon. Partly sunny, with a high near 67. South wind 8 to 16 mph, with gusts as high as 24 mph. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.

    High: 67 °F

    Partly Sunny
    then Rain
    Likely

  • Thursday Night

    Thursday Night: A 50 percent chance of rain before midnight. Partly cloudy, with a low around 35. South wind 10 to 16 mph becoming west after midnight. Winds could gust as high as 24 mph.

    Low: 35 °F

    Chance Rain
    then Mostly
    Clear

  • Friday

    Friday: Mostly sunny, with a high near 47. Breezy.

    High: 47 °F

    Mostly Sunny
    and Breezy

  • Friday Night

    Friday Night: Mostly cloudy, with a low around 28.

    Low: 28 °F

    Mostly Cloudy

Detailed Forecast

Overnight
Patchy fog after 4am. Otherwise, mostly cloudy, with a low around 39. South wind around 7 mph, with gusts as high as 16 mph.
Tuesday
Patchy fog before 10am. Otherwise, mostly cloudy, with a high near 59. South wind 8 to 16 mph, with gusts as high as 29 mph.
Tuesday Night
A 40 percent chance of rain after midnight. Cloudy, then gradually becoming partly cloudy, with a low around 52. Breezy, with a south wind 16 to 21 mph, with gusts as high as 32 mph.
Wednesday
Sunny, with a high near 68. West southwest wind 9 to 18 mph, with gusts as high as 30 mph.
Wednesday Night
Increasing clouds, with a low around 45. Southwest wind around 7 mph becoming south southeast after midnight.
Thursday
Rain likely after noon. Partly sunny, with a high near 67. South wind 8 to 16 mph, with gusts as high as 24 mph. Chance of precipitation is 60%. New precipitation amounts between a tenth and quarter of an inch possible.
Thursday Night
A 50 percent chance of rain before midnight. Partly cloudy, with a low around 35. South wind 10 to 16 mph becoming west after midnight. Winds could gust as high as 24 mph.
Friday
Mostly sunny, with a high near 47. Breezy.
Friday Night
Mostly cloudy, with a low around 28.
Saturday
Partly sunny, with a high near 44.
Saturday Night
Partly cloudy, with a low around 25.
Sunday
Mostly sunny, with a high near 38.
Sunday Night
Partly cloudy, with a low around 18.
Monday
Mostly sunny, with a high near 37.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Sullivan IL
 39.59°N 88.61°W (Elev. 669 ft)
Last Update:
12:36 am CST Feb 17, 2026
Forecast Valid:
1am CST Feb 17, 2026-6pm CST Feb 23, 2026
 
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Additional Resources

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High Temperature

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Chance of Precipitation