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

51°F

11°C

Humidity 39%
Wind Speed SE 8 G 18 mph
Barometer 30.48 in (1032.7 mb)
Dewpoint 27°F (-3°C)
Visibility 10.00 mi
Wind Chill48°F (9°C)
Last update 28 Mar 3:53 pm CDT
Extended Forecast for

Sullivan IL

  • Tonight

    Tonight: Increasing clouds, with a low around 38. South wind 7 to 9 mph, with gusts as high as 16 mph.

    Low: 38 °F

    Increasing
    Clouds

  • Sunday

    Sunday: Mostly sunny, with a high near 64. South southwest wind 9 to 16 mph, with gusts as high as 25 mph.

    High: 64 °F

    Mostly Sunny

  • Sunday Night

    Sunday Night: Mostly cloudy, with a low around 52. South southwest wind 11 to 13 mph, with gusts as high as 22 mph.

    Low: 52 °F

    Mostly Cloudy

  • Monday

    Monday: Mostly sunny, with a high near 77. Breezy, with a south southwest wind 13 to 20 mph, with gusts as high as 30 mph.

    High: 77 °F

    Partly Sunny
    then Mostly
    Sunny and
    Breezy

  • Monday Night

    Monday Night: Partly cloudy, with a low around 62. South wind 16 to 18 mph, with gusts as high as 30 mph.

    Low: 62 °F

    Partly Cloudy

  • Tuesday

    Tuesday: Showers and thunderstorms likely after 1pm. Partly sunny, with a high near 79. Breezy, with a southwest wind 18 to 23 mph, with gusts as high as 36 mph. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

    High: 79 °F

    Breezy.
    Partly Sunny
    then T-storms
    Likely

  • Tuesday Night

    Tuesday Night: Showers and possibly a thunderstorm. Low around 42. West southwest wind 15 to 17 mph becoming north after midnight. Winds could gust as high as 25 mph. Chance of precipitation is 80%. New rainfall amounts between a half and three quarters of an inch possible.

    Low: 42 °F

    T-storms

  • Wednesday

    Wednesday: A 50 percent chance of showers. Mostly cloudy, with a high near 51.

    High: 51 °F

    Chance
    Showers

  • Wednesday Night

    Wednesday Night: A 50 percent chance of showers. Mostly cloudy, with a low around 38.

    Low: 38 °F

    Chance
    Showers

Detailed Forecast

Tonight
Increasing clouds, with a low around 38. South wind 7 to 9 mph, with gusts as high as 16 mph.
Sunday
Mostly sunny, with a high near 64. South southwest wind 9 to 16 mph, with gusts as high as 25 mph.
Sunday Night
Mostly cloudy, with a low around 52. South southwest wind 11 to 13 mph, with gusts as high as 22 mph.
Monday
Mostly sunny, with a high near 77. Breezy, with a south southwest wind 13 to 20 mph, with gusts as high as 30 mph.
Monday Night
Partly cloudy, with a low around 62. South wind 16 to 18 mph, with gusts as high as 30 mph.
Tuesday
Showers and thunderstorms likely after 1pm. Partly sunny, with a high near 79. Breezy, with a southwest wind 18 to 23 mph, with gusts as high as 36 mph. Chance of precipitation is 60%. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.
Tuesday Night
Showers and possibly a thunderstorm. Low around 42. West southwest wind 15 to 17 mph becoming north after midnight. Winds could gust as high as 25 mph. Chance of precipitation is 80%. New rainfall amounts between a half and three quarters of an inch possible.
Wednesday
A 50 percent chance of showers. Mostly cloudy, with a high near 51.
Wednesday Night
A 50 percent chance of showers. Mostly cloudy, with a low around 38.
Thursday
Showers likely. Mostly cloudy, with a high near 54. Chance of precipitation is 60%.
Thursday Night
A chance of showers. Mostly cloudy, with a low around 41.
Friday
A chance of showers. Mostly cloudy, with a high near 67.
Friday Night
A chance of showers. Mostly cloudy, with a low around 51.
Saturday
Showers likely. Mostly cloudy, with a high near 66. Breezy.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Sullivan IL
 39.59°N 88.61°W (Elev. 669 ft)
Last Update:
2:57 pm CDT Mar 28, 2026
Forecast Valid:
4pm CDT Mar 28, 2026-6pm CDT Apr 4, 2026
 
Forecast Discussion
 
Get as KML Get as XML

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