National Oceanic and Atmospheric Administration National Weather Service United States Department of Commerce
Current conditions at

Chicago/Waukegan Regional Airport (KUGN)

Lat: 42.43°NLon: 87.86°WElev: 709ft.

Fair

37°F

3°C

Humidity 93%
Wind Speed Calm
Barometer 29.94 in (1014.3 mb)
Dewpoint 35°F (2°C)
Visibility 10.00 mi
Last update 21 Mar 4:51 am CDT
Extended Forecast for

Grayslake IL

  • Today

    Today: Mostly sunny, with a high near 72. East southeast wind 5 to 10 mph becoming south southwest 10 to 15 mph in the afternoon. Winds could gust as high as 30 mph.

    High: 72 °F

    Mostly Sunny

  • Tonight

    Tonight: Increasing clouds, with a low around 40. Southwest wind 5 to 15 mph becoming north northeast after midnight. Winds could gust as high as 25 mph.

    Low: 40 °F

    Increasing
    Clouds

  • Sunday

    Sunday: A 40 percent chance of rain, mainly before 4pm. Cloudy, with a temperature falling to around 38 by 5pm. Breezy, with a north northeast wind 15 to 20 mph, with gusts as high as 30 mph.

    High: 41 °F⇓

    Chance Rain
    and Breezy

  • Sunday Night

    Sunday Night: A 10 percent chance of rain before 7pm. Mostly cloudy, with a low around 27. North wind 5 to 15 mph, with gusts as high as 25 mph.

    Low: 27 °F

    Slight Chance
    Rain then
    Mostly Cloudy

  • Monday

    Monday: Sunny, with a high near 44. North wind around 5 mph, with gusts as high as 10 mph.

    High: 44 °F

    Sunny

  • Monday Night

    Monday Night: Mostly cloudy, with a low around 30.

    Low: 30 °F

    Mostly Cloudy

  • Tuesday

    Tuesday: Mostly cloudy, with a high near 55.

    High: 55 °F

    Mostly Cloudy

  • Tuesday Night

    Tuesday Night: Mostly cloudy, with a low around 37.

    Low: 37 °F

    Mostly Cloudy

  • Wednesday

    Wednesday: Mostly cloudy, with a high near 51.

    High: 51 °F

    Mostly Cloudy

Detailed Forecast

Today
Mostly sunny, with a high near 72. East southeast wind 5 to 10 mph becoming south southwest 10 to 15 mph in the afternoon. Winds could gust as high as 30 mph.
Tonight
Increasing clouds, with a low around 40. Southwest wind 5 to 15 mph becoming north northeast after midnight. Winds could gust as high as 25 mph.
Sunday
A 40 percent chance of rain, mainly before 4pm. Cloudy, with a temperature falling to around 38 by 5pm. Breezy, with a north northeast wind 15 to 20 mph, with gusts as high as 30 mph.
Sunday Night
A 10 percent chance of rain before 7pm. Mostly cloudy, with a low around 27. North wind 5 to 15 mph, with gusts as high as 25 mph.
Monday
Sunny, with a high near 44. North wind around 5 mph, with gusts as high as 10 mph.
Monday Night
Mostly cloudy, with a low around 30.
Tuesday
Mostly cloudy, with a high near 55.
Tuesday Night
Mostly cloudy, with a low around 37.
Wednesday
Mostly cloudy, with a high near 51.
Wednesday Night
Mostly cloudy, with a low around 42.
Thursday
A chance of showers. Mostly cloudy, with a high near 60.
Thursday Night
Mostly cloudy, with a low around 30.
Friday
Partly sunny, with a high near 42.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Grayslake IL
 42.35°N 88.02°W
Last Update:
4:25 am CDT Mar 21, 2026
Forecast Valid:
5am CDT Mar 21, 2026-6pm CDT Mar 27, 2026
 
Forecast Discussion
 
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Additional Resources

Radar & Satellite Image

Link to Local Radar Data Link to Satellite Data

Hourly Weather Forecast

National Digital Forecast Database

National Digital Forecast Database Maximum Temperature Forecast

High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation