National Weather Service Forecast for: Decatur IL
Issued by: National Weather Service Lincoln, IL
Updated: 9:36 pm CST Dec 17, 2025
 
Tonight

Tonight: A chance of drizzle, mainly after 3am. Cloudy, with a low around 36. Breezy, with a south wind 14 to 22 mph, with gusts as high as 37 mph.
Chance
Drizzle and
Breezy

 Thursday

Thursday: Rain and possibly a thunderstorm before 2pm, then a chance of showers, mainly between 2pm and 5pm. Temperature rising to near 51 by 8am, then falling to around 39 during the remainder of the day. Breezy, with a south wind 19 to 24 mph becoming west 11 to 16 mph in the afternoon. Winds could gust as high as 43 mph. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.
Showers and
Breezy

 Thursday
Night
Thursday Night: A slight chance of rain before 8pm, then a chance of snow between 8pm and midnight. Mostly cloudy, with a low around 18. Wind chill values between 2 and 12. Blustery, with a west northwest wind 18 to 25 mph, with gusts as high as 37 mph. Chance of precipitation is 30%.
Blustery.
Chance
Rain/Snow
then Mostly
Cloudy
 Friday

Friday: Sunny, with a high near 31. Wind chill values between 2 and 12. West northwest wind 9 to 18 mph becoming south in the afternoon. Winds could gust as high as 26 mph.
Sunny


 Friday
Night
Friday Night: Increasing clouds, with a low around 26. South wind 9 to 18 mph, with gusts as high as 25 mph.
Increasing
Clouds

 Saturday

Saturday: Partly sunny, with a high near 48. South wind 11 to 18 mph becoming west northwest in the afternoon. Winds could gust as high as 25 mph.
Partly Sunny


 Saturday
Night
Saturday Night: Partly cloudy, with a low around 22. Northwest wind 7 to 10 mph, with gusts as high as 17 mph.
Partly Cloudy


 Sunday

Sunday: Sunny, with a high near 37.
Sunny


 Sunday
Night
Sunday Night: Mostly cloudy, with a low around 25.
Mostly Cloudy
Lo 36 °F Hi 51 °F⇓ Lo 18 °F Hi 31 °F Lo 26 °F Hi 48 °F Lo 22 °F Hi 37 °F Lo 25 °F

 

Tonight
 
 A chance of drizzle, mainly after 3am. Cloudy, with a low around 36. Breezy, with a south wind 14 to 22 mph, with gusts as high as 37 mph.
Thursday
 
 Rain and possibly a thunderstorm before 2pm, then a chance of showers, mainly between 2pm and 5pm. Temperature rising to near 51 by 8am, then falling to around 39 during the remainder of the day. Breezy, with a south wind 19 to 24 mph becoming west 11 to 16 mph in the afternoon. Winds could gust as high as 43 mph. Chance of precipitation is 90%. New precipitation amounts between a quarter and half of an inch possible.
Thursday Night
 
 A slight chance of rain before 8pm, then a chance of snow between 8pm and midnight. Mostly cloudy, with a low around 18. Wind chill values between 2 and 12. Blustery, with a west northwest wind 18 to 25 mph, with gusts as high as 37 mph. Chance of precipitation is 30%.
Friday
 
 Sunny, with a high near 31. Wind chill values between 2 and 12. West northwest wind 9 to 18 mph becoming south in the afternoon. Winds could gust as high as 26 mph.
Friday Night
 
 Increasing clouds, with a low around 26. South wind 9 to 18 mph, with gusts as high as 25 mph.
Saturday
 
 Partly sunny, with a high near 48. South wind 11 to 18 mph becoming west northwest in the afternoon. Winds could gust as high as 25 mph.
Saturday Night
 
 Partly cloudy, with a low around 22. Northwest wind 7 to 10 mph, with gusts as high as 17 mph.
Sunday
 
 Sunny, with a high near 37.
Sunday Night
 
 Mostly cloudy, with a low around 25.
Monday
 
 Partly sunny, with a high near 42.
Monday Night
 
 Mostly cloudy, with a low around 36.
Tuesday
 
 Partly sunny, with a high near 51.
Tuesday Night
 
 Mostly cloudy, with a low around 34.
Wednesday
 
 Partly sunny, with a high near 51.

 

Forecast from NOAA-NWS for Decatur IL.