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Hazardous Weather Conditions

Current conditions at

Decatur Airport (KDEC)

Lat: 39.83°NLon: 88.87°WElev: 670ft.

Fair

45°F

7°C

Humidity 52%
Wind Speed N 8 mph
Barometer 30.25 in (1024.6 mb)
Dewpoint 28°F (-2°C)
Visibility 10.00 mi
Wind Chill41°F (5°C)
Last update 19 Apr 10:54 pm CDT
Extended Forecast for

Forsyth IL

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

  • Tonight

    Tonight: Widespread frost, mainly after 4am. Otherwise, clear, with a low around 32. North northeast wind around 6 mph.

    Low: 32 °F

    Frost

  • Monday

    Monday: Widespread frost before 8am. Otherwise, sunny, with a high near 61. Northeast wind 5 to 7 mph becoming south in the afternoon.

    High: 61 °F

    Frost then
    Sunny

  • Monday Night

    Monday Night: Mostly clear, with a low around 47. South wind 8 to 13 mph, with gusts as high as 21 mph.

    Low: 47 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 77. Breezy, with a southwest wind 13 to 22 mph, with gusts as high as 30 mph.

    High: 77 °F

    Sunny and
    Breezy

  • Tuesday Night

    Tuesday Night: A 30 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 59. Southwest wind 11 to 15 mph, with gusts as high as 23 mph.

    Low: 59 °F

    Chance
    T-storms

  • Wednesday

    Wednesday: Mostly sunny, with a high near 78. West southwest wind around 10 mph, with gusts as high as 16 mph.

    High: 78 °F

    Mostly Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 57. South wind 9 to 11 mph, with gusts as high as 18 mph.

    Low: 57 °F

    Mostly Clear

  • Thursday

    Thursday: Sunny, with a high near 80. Breezy.

    High: 80 °F

    Sunny and
    Breezy

  • Thursday Night

    Thursday Night: Showers likely, mainly after 1am. Mostly cloudy, with a low around 61. Breezy. Chance of precipitation is 70%.

    Low: 61 °F

    Breezy.
    Chance
    Showers then
    Showers
    Likely

Detailed Forecast

Tonight
Widespread frost, mainly after 4am. Otherwise, clear, with a low around 32. North northeast wind around 6 mph.
Monday
Widespread frost before 8am. Otherwise, sunny, with a high near 61. Northeast wind 5 to 7 mph becoming south in the afternoon.
Monday Night
Mostly clear, with a low around 47. South wind 8 to 13 mph, with gusts as high as 21 mph.
Tuesday
Sunny, with a high near 77. Breezy, with a southwest wind 13 to 22 mph, with gusts as high as 30 mph.
Tuesday Night
A 30 percent chance of showers and thunderstorms before 1am. Partly cloudy, with a low around 59. Southwest wind 11 to 15 mph, with gusts as high as 23 mph.
Wednesday
Mostly sunny, with a high near 78. West southwest wind around 10 mph, with gusts as high as 16 mph.
Wednesday Night
Mostly clear, with a low around 57. South wind 9 to 11 mph, with gusts as high as 18 mph.
Thursday
Sunny, with a high near 80. Breezy.
Thursday Night
Showers likely, mainly after 1am. Mostly cloudy, with a low around 61. Breezy. Chance of precipitation is 70%.
Friday
Showers likely, mainly before 1pm. Mostly cloudy, with a high near 74. Chance of precipitation is 70%.
Friday Night
A chance of showers. Partly cloudy, with a low around 49.
Saturday
Mostly sunny, with a high near 68.
Saturday Night
Partly cloudy, with a low around 48.
Sunday
Mostly sunny, with a high near 68.
Basemap Options
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Forsyth IL
 39.93°N 88.96°W (Elev. 650 ft)
Last Update:
10:36 pm CDT Apr 19, 2026
Forecast Valid:
11pm CDT Apr 19, 2026-6pm CDT Apr 26, 2026
 
Forecast Discussion
 
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Additional Resources

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Hourly Weather Forecast

National Digital Forecast Database

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation