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Hazardous Weather Conditions

Current conditions at

Mattoon / Charleston, Coles County Memorial Airport (KMTO)

Lat: 39.48°NLon: 88.28°WElev: 722ft.

Overcast

68°F

20°C

Humidity 84%
Wind Speed NE 9 mph
Barometer 30.08 in (1018.2 mb)
Dewpoint 63°F (17°C)
Visibility 9.00 mi
Last update 15 Oct 12:53 am CDT
Extended Forecast for

Sullivan IL

  • Overnight

    Overnight: Mostly cloudy, with a low around 62. East northeast wind around 7 mph.

    Low: 62 °F

    Mostly Cloudy

  • Thursday

    Thursday: Showers and thunderstorms likely, then showers and possibly a thunderstorm after 3pm. High near 77. East wind 6 to 11 mph becoming south in the afternoon. Winds could gust as high as 18 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 77 °F

    Showers

  • Thursday Night

    Thursday Night: Showers likely and possibly a thunderstorm before 3am, then a chance of showers. Increasing clouds, with a low around 46. Southwest wind 11 to 17 mph becoming west northwest after midnight. Winds could gust as high as 26 mph. Chance of precipitation is 70%. New precipitation amounts between a quarter and half of an inch possible.

    Low: 46 °F

    Showers
    Likely

  • Friday

    Friday: A 30 percent chance of showers after 5pm. Partly sunny, with a high near 56. Breezy, with a northwest wind 17 to 20 mph, with gusts as high as 31 mph.

    High: 56 °F

    Mostly Cloudy
    then Chance
    Showers and
    Breezy

  • Friday Night

    Friday Night: Cloudy during the early evening, then gradual clearing, with a low around 36. North wind 10 to 14 mph, with gusts as high as 22 mph.

    Low: 36 °F

    Gradual
    Clearing

  • Saturday

    Saturday: Areas of frost before 8am. Otherwise, sunny, with a high near 59. North northeast wind 3 to 7 mph.

    High: 59 °F

    Areas Frost
    then Sunny

  • Saturday Night

    Saturday Night: Areas of frost after 2am. Otherwise, clear, with a low around 34. Light and variable wind.

    Low: 34 °F

    Clear then
    Areas Frost

  • Sunday

    Sunday: Widespread frost, mainly before 7am. Otherwise, sunny, with a high near 68.

    High: 68 °F

    Frost then
    Sunny

  • Sunday Night

    Sunday Night: Clear, with a low around 37.

    Low: 37 °F

    Clear

Detailed Forecast

Overnight
Mostly cloudy, with a low around 62. East northeast wind around 7 mph.
Thursday
Showers and thunderstorms likely, then showers and possibly a thunderstorm after 3pm. High near 77. East wind 6 to 11 mph becoming south in the afternoon. Winds could gust as high as 18 mph. Chance of precipitation is 80%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Thursday Night
Showers likely and possibly a thunderstorm before 3am, then a chance of showers. Increasing clouds, with a low around 46. Southwest wind 11 to 17 mph becoming west northwest after midnight. Winds could gust as high as 26 mph. Chance of precipitation is 70%. New precipitation amounts between a quarter and half of an inch possible.
Friday
A 30 percent chance of showers after 5pm. Partly sunny, with a high near 56. Breezy, with a northwest wind 17 to 20 mph, with gusts as high as 31 mph.
Friday Night
Cloudy during the early evening, then gradual clearing, with a low around 36. North wind 10 to 14 mph, with gusts as high as 22 mph.
Saturday
Areas of frost before 8am. Otherwise, sunny, with a high near 59. North northeast wind 3 to 7 mph.
Saturday Night
Areas of frost after 2am. Otherwise, clear, with a low around 34. Light and variable wind.
Sunday
Widespread frost, mainly before 7am. Otherwise, sunny, with a high near 68.
Sunday Night
Clear, with a low around 37.
Monday
Mostly sunny, with a high near 73.
Monday Night
Partly cloudy, with a low around 40.
Tuesday
Mostly sunny, with a high near 74.
Tuesday Night
Mostly clear, with a low around 42.
Wednesday
Sunny, with a high near 76.
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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:
1:21 am CDT Oct 15, 2026
Forecast Valid:
1am CDT Oct 15, 2026-6pm CDT Oct 21, 2026
 
Forecast Discussion
 
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Additional Resources

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation