National Weather Service Forecast for: De Kalb IL
Issued by: National Weather Service Chicago, IL
Updated: 9:46 am CDT May 4, 2026
 
This
Afternoon
This Afternoon: Patchy blowing dust. Sunny, with a high near 78. Breezy, with a west southwest wind around 20 mph, with gusts as high as 30 mph.
Patchy
Blowing Dust
and Breezy
 Tonight

Tonight: Scattered showers and thunderstorms before 2am, then isolated showers between 2am and 4am. Mostly cloudy, with a low around 47. West southwest wind 10 to 15 mph becoming north after midnight. Winds could gust as high as 20 mph. Chance of precipitation is 50%.
Scattered
T-storms then
Isolated
Showers
 Tuesday

Tuesday: A 20 percent chance of showers after 7am. Mostly cloudy, with a high near 55. North wind 5 to 10 mph.
Slight Chance
Showers

 Tuesday
Night
Tuesday Night: Mostly cloudy, with a low around 38. North wind around 5 mph, with gusts as high as 15 mph.
Mostly Cloudy

 Wednesday

Wednesday: Partly sunny, with a high near 56. Northwest wind 5 to 10 mph, with gusts as high as 15 mph.
Partly Sunny

 Wednesday
Night
Wednesday Night: Mostly cloudy, with a low around 38.
Mostly Cloudy

 Thursday

Thursday: Partly sunny, with a high near 58.
Partly Sunny

 Thursday
Night
Thursday Night: Partly cloudy, with a low around 41.
Partly Cloudy

 Friday

Friday: Mostly sunny, with a high near 63.
Mostly Sunny
Hi 78 °F Lo 47 °F Hi 55 °F Lo 38 °F Hi 56 °F Lo 38 °F Hi 58 °F Lo 41 °F Hi 63 °F

Hazardous Weather Outlook
 

This Afternoon
 
 Patchy blowing dust. Sunny, with a high near 78. Breezy, with a west southwest wind around 20 mph, with gusts as high as 30 mph.
Tonight
 
 Scattered showers and thunderstorms before 2am, then isolated showers between 2am and 4am. Mostly cloudy, with a low around 47. West southwest wind 10 to 15 mph becoming north after midnight. Winds could gust as high as 20 mph. Chance of precipitation is 50%.
Tuesday
 
 A 20 percent chance of showers after 7am. Mostly cloudy, with a high near 55. North wind 5 to 10 mph.
Tuesday Night
 
 Mostly cloudy, with a low around 38. North wind around 5 mph, with gusts as high as 15 mph.
Wednesday
 
 Partly sunny, with a high near 56. Northwest wind 5 to 10 mph, with gusts as high as 15 mph.
Wednesday Night
 
 Mostly cloudy, with a low around 38.
Thursday
 
 Partly sunny, with a high near 58.
Thursday Night
 
 Partly cloudy, with a low around 41.
Friday
 
 Mostly sunny, with a high near 63.
Friday Night
 
 Partly cloudy, with a low around 41.
Saturday
 
 Sunny, with a high near 67.
Saturday Night
 
 Partly cloudy, with a low around 45.
Sunday
 
 Partly sunny, with a high near 66.

 

Forecast from NOAA-NWS for De Kalb IL.