National Weather Service Forecast for: Decatur IL
Issued by: National Weather Service Lincoln, IL
Updated: 1:46 am CST Dec 23, 2025
 
Overnight

Overnight: Mostly cloudy, with a low around 40. Southwest wind around 10 mph, with gusts as high as 17 mph.
Mostly Cloudy

 Tuesday

Tuesday: Mostly sunny, with a high near 57. Southwest wind 6 to 9 mph becoming north northwest in the afternoon. Winds could gust as high as 17 mph.
Mostly Sunny

 Tuesday
Night
Tuesday Night: Partly cloudy, with a low around 33. Light and variable wind becoming east 5 to 7 mph after midnight.
Partly Cloudy

 Wednesday

Wednesday: Patchy drizzle after noon. Mostly cloudy, with a high near 55. Southeast wind 7 to 10 mph, with gusts as high as 17 mph.
Mostly Cloudy
then Patchy
Drizzle
 Wednesday
Night
Wednesday Night: Patchy drizzle with a chance of rain before midnight, then a chance of rain after midnight. Patchy fog before midnight. Otherwise, mostly cloudy, with a low around 47. South wind 5 to 9 mph becoming north after midnight. Chance of precipitation is 50%.
Chance Rain
and Patchy
Fog
 Christmas
Day
Christmas Day: Mostly cloudy, with a high near 57. North wind 5 to 7 mph becoming east in the afternoon.
Mostly Cloudy

 Thursday
Night
Thursday Night: A 30 percent chance of rain. Mostly cloudy, with a low around 51. East wind 7 to 10 mph becoming south southwest after midnight. Winds could gust as high as 17 mph.
Chance Rain

 Friday

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

 Friday
Night
Friday Night: Mostly cloudy, with a low around 46.
Mostly Cloudy
Lo 40 °F Hi 57 °F Lo 33 °F Hi 55 °F Lo 47 °F Hi 57 °F Lo 51 °F Hi 65 °F Lo 46 °F

 

Overnight
 
 Mostly cloudy, with a low around 40. Southwest wind around 10 mph, with gusts as high as 17 mph.
Tuesday
 
 Mostly sunny, with a high near 57. Southwest wind 6 to 9 mph becoming north northwest in the afternoon. Winds could gust as high as 17 mph.
Tuesday Night
 
 Partly cloudy, with a low around 33. Light and variable wind becoming east 5 to 7 mph after midnight.
Wednesday
 
 Patchy drizzle after noon. Mostly cloudy, with a high near 55. Southeast wind 7 to 10 mph, with gusts as high as 17 mph.
Wednesday Night
 
 Patchy drizzle with a chance of rain before midnight, then a chance of rain after midnight. Patchy fog before midnight. Otherwise, mostly cloudy, with a low around 47. South wind 5 to 9 mph becoming north after midnight. Chance of precipitation is 50%.
Christmas Day
 
 Mostly cloudy, with a high near 57. North wind 5 to 7 mph becoming east in the afternoon.
Thursday Night
 
 A 30 percent chance of rain. Mostly cloudy, with a low around 51. East wind 7 to 10 mph becoming south southwest after midnight. Winds could gust as high as 17 mph.
Friday
 
 Mostly sunny, with a high near 65.
Friday Night
 
 Mostly cloudy, with a low around 46.
Saturday
 
 Mostly cloudy, with a high near 65.
Saturday Night
 
 Mostly cloudy, with a low around 28.
Sunday
 
 Mostly sunny, with a high near 35. Breezy.
Sunday Night
 
 Mostly clear, with a low around 12.
Monday
 
 Sunny, with a high near 25.

 

Forecast from NOAA-NWS for Decatur IL.