National Weather Service Forecast for: Decatur IL
Issued by: National Weather Service Lincoln, IL
Updated: 3:36 pm CST Dec 22, 2025
 
Tonight

Tonight: Mostly cloudy, with a low around 42. Southwest wind 9 to 11 mph, with gusts as high as 18 mph.
Mostly Cloudy

 Tuesday

Tuesday: Mostly sunny, with a high near 56. Southwest wind 5 to 9 mph becoming north northwest in the afternoon. Winds could gust as high as 16 mph.
Mostly Sunny

 Tuesday
Night
Tuesday Night: Partly cloudy, with a low around 35. Light and variable wind becoming east 5 to 7 mph after midnight.
Partly Cloudy

 Wednesday

Wednesday: Cloudy, with a high near 54. Southeast wind 7 to 10 mph, with gusts as high as 17 mph.
Cloudy

 Wednesday
Night
Wednesday Night: A 40 percent chance of rain before midnight. Mostly cloudy, with a low around 49. South southeast wind 5 to 8 mph becoming west northwest after midnight.
Chance Rain
then Mostly
Cloudy
 Christmas
Day
Christmas Day: Mostly cloudy, with a high near 60. West northwest wind 5 to 8 mph becoming southeast in the morning.
Mostly Cloudy

 Thursday
Night
Thursday Night: Mostly cloudy, with a low around 54. Southeast wind 8 to 13 mph becoming southwest after midnight. Winds could gust as high as 21 mph.
Mostly Cloudy

 Friday

Friday: Mostly sunny, with a high near 65.
Mostly Sunny

 Friday
Night
Friday Night: Partly cloudy, with a low around 44.
Partly Cloudy
Lo 42 °F Hi 56 °F Lo 35 °F Hi 54 °F Lo 49 °F Hi 60 °F Lo 54 °F Hi 65 °F Lo 44 °F

 

Tonight
 
 Mostly cloudy, with a low around 42. Southwest wind 9 to 11 mph, with gusts as high as 18 mph.
Tuesday
 
 Mostly sunny, with a high near 56. Southwest wind 5 to 9 mph becoming north northwest in the afternoon. Winds could gust as high as 16 mph.
Tuesday Night
 
 Partly cloudy, with a low around 35. Light and variable wind becoming east 5 to 7 mph after midnight.
Wednesday
 
 Cloudy, with a high near 54. Southeast wind 7 to 10 mph, with gusts as high as 17 mph.
Wednesday Night
 
 A 40 percent chance of rain before midnight. Mostly cloudy, with a low around 49. South southeast wind 5 to 8 mph becoming west northwest after midnight.
Christmas Day
 
 Mostly cloudy, with a high near 60. West northwest wind 5 to 8 mph becoming southeast in the morning.
Thursday Night
 
 Mostly cloudy, with a low around 54. Southeast wind 8 to 13 mph becoming southwest after midnight. Winds could gust as high as 21 mph.
Friday
 
 Mostly sunny, with a high near 65.
Friday Night
 
 Partly cloudy, with a low around 44.
Saturday
 
 Mostly cloudy, with a high near 62.
Saturday Night
 
 Mostly cloudy, with a low around 32.
Sunday
 
 Mostly sunny, with a high near 41.
Sunday Night
 
 Mostly clear, with a low around 16.
Monday
 
 Sunny, with a high near 30.

 

Forecast from NOAA-NWS for Decatur IL.