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Hazardous Weather Conditions

Current conditions at

Decatur Airport (KDEC)

Lat: 39.83°NLon: 88.87°WElev: 670ft.

Overcast

58°F

14°C

Humidity 32%
Wind Speed W 15 G 35 mph
Barometer 30.16 in (1021.6 mb)
Dewpoint 28°F (-2°C)
Visibility 10.00 mi
Last update 19 Apr 2:54 pm CDT
Extended Forecast for

4 Miles WSW Sullivan IL

Frost Advisory April 20, 01:00am until April 20, 08:00am
Click here for hazard details and duration
Frost Advisory

  • This Afternoon

    This Afternoon: Partly sunny, with a high near 60. West northwest wind around 18 mph, with gusts as high as 38 mph.

    High: 60 °F

    Partly Sunny

  • Tonight

    Tonight: Areas of frost after 3am. Otherwise, mostly clear, with a low around 34. North northwest wind 8 to 13 mph becoming light north northeast after midnight. Winds could gust as high as 23 mph.

    Low: 34 °F

    Mostly Clear
    then Areas
    Frost

  • Monday

    Monday: Areas of frost before 8am. Otherwise, sunny, with a high near 59. Light and variable wind becoming east around 6 mph in the afternoon.

    High: 59 °F

    Areas Frost
    then Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 45. South wind 6 to 10 mph, with gusts as high as 18 mph.

    Low: 45 °F

    Mostly Clear

  • Tuesday

    Tuesday: Mostly sunny, with a high near 75. Southwest wind 10 to 16 mph, with gusts as high as 29 mph.

    High: 75 °F

    Mostly Sunny

  • Tuesday Night

    Tuesday Night: Partly cloudy, with a low around 57. Southwest wind 9 to 11 mph, with gusts as high as 21 mph.

    Low: 57 °F

    Partly Cloudy

  • Wednesday

    Wednesday: Mostly sunny, with a high near 76. West southwest wind around 9 mph, with gusts as high as 15 mph.

    High: 76 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 56.

    Low: 56 °F

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 79.

    High: 79 °F

    Sunny

Detailed Forecast

This Afternoon
Partly sunny, with a high near 60. West northwest wind around 18 mph, with gusts as high as 38 mph.
Tonight
Areas of frost after 3am. Otherwise, mostly clear, with a low around 34. North northwest wind 8 to 13 mph becoming light north northeast after midnight. Winds could gust as high as 23 mph.
Monday
Areas of frost before 8am. Otherwise, sunny, with a high near 59. Light and variable wind becoming east around 6 mph in the afternoon.
Monday Night
Mostly clear, with a low around 45. South wind 6 to 10 mph, with gusts as high as 18 mph.
Tuesday
Mostly sunny, with a high near 75. Southwest wind 10 to 16 mph, with gusts as high as 29 mph.
Tuesday Night
Partly cloudy, with a low around 57. Southwest wind 9 to 11 mph, with gusts as high as 21 mph.
Wednesday
Mostly sunny, with a high near 76. West southwest wind around 9 mph, with gusts as high as 15 mph.
Wednesday Night
Mostly clear, with a low around 56.
Thursday
Sunny, with a high near 79.
Thursday Night
Showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 61. Chance of precipitation is 70%.
Friday
Showers likely and possibly a thunderstorm. Mostly cloudy, with a high near 74.
Friday Night
A chance of showers. Mostly cloudy, with a low around 49.
Saturday
Mostly sunny, with a high near 68.
Basemap Options
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
4 Miles WSW Sullivan IL
 39.57°N 88.67°W (Elev. 676 ft)
Last Update:
1:26 pm CDT Apr 19, 2026
Forecast Valid:
3pm CDT Apr 19, 2026-6pm CDT Apr 25, 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