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Hazardous Weather Conditions

Current conditions at

Chicago/Waukegan Regional Airport (KUGN)

Lat: 42.43°NLon: 87.86°WElev: 709ft.

A Few Clouds

86°F

30°C

Humidity 55%
Wind Speed S 10 mph
Barometer 30.03 in (1015.6 mb)
Dewpoint 68°F (20°C)
Visibility 10.00 mi
Heat Index89°F (32°C)
Last update 15 Jul 12:51 pm CDT
Extended Forecast for

Grayslake IL

  • This Afternoon

    This Afternoon: Mostly sunny, with a high near 87. South southeast wind around 10 mph.

    High: 87 °F

    Mostly Sunny

  • Tonight

    Tonight: Partly cloudy, with a low around 71. East southeast wind around 5 mph becoming calm in the evening.

    Low: 71 °F

    Partly Cloudy

  • Wednesday

    Wednesday: A 40 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 88. Heat index values as high as 96. Southwest wind 5 to 15 mph, with gusts as high as 20 mph.

    High: 88 °F

    Mostly Sunny
    then Chance
    T-storms

  • Wednesday Night

    Wednesday Night: Showers and thunderstorms likely, mainly before 1am. Mostly cloudy, with a low around 65. Southwest wind 5 to 10 mph, with gusts as high as 15 mph. Chance of precipitation is 60%.

    Low: 65 °F

    T-storms
    Likely

  • Thursday

    Thursday: A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 73. Northwest wind around 10 mph becoming north northeast in the afternoon. Winds could gust as high as 20 mph.

    High: 73 °F

    Chance
    T-storms

  • Thursday Night

    Thursday Night: Mostly cloudy, with a low around 59.

    Low: 59 °F

    Mostly Cloudy

  • Friday

    Friday: Mostly sunny, with a high near 76.

    High: 76 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 63.

    Low: 63 °F

    Partly Cloudy

  • Saturday

    Saturday: A chance of showers, with thunderstorms also possible after 1pm. Partly sunny, with a high near 82.

    High: 82 °F

    Chance
    Showers then
    Chance
    T-storms

Detailed Forecast

This Afternoon
Mostly sunny, with a high near 87. South southeast wind around 10 mph.
Tonight
Partly cloudy, with a low around 71. East southeast wind around 5 mph becoming calm in the evening.
Wednesday
A 40 percent chance of showers and thunderstorms after 1pm. Mostly sunny, with a high near 88. Heat index values as high as 96. Southwest wind 5 to 15 mph, with gusts as high as 20 mph.
Wednesday Night
Showers and thunderstorms likely, mainly before 1am. Mostly cloudy, with a low around 65. Southwest wind 5 to 10 mph, with gusts as high as 15 mph. Chance of precipitation is 60%.
Thursday
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 73. Northwest wind around 10 mph becoming north northeast in the afternoon. Winds could gust as high as 20 mph.
Thursday Night
Mostly cloudy, with a low around 59.
Friday
Mostly sunny, with a high near 76.
Friday Night
Partly cloudy, with a low around 63.
Saturday
A chance of showers, with thunderstorms also possible after 1pm. Partly sunny, with a high near 82.
Saturday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 67.
Sunday
A chance of showers. Partly sunny, with a high near 81.
Sunday Night
A chance of showers. Mostly cloudy, with a low around 65.
Monday
A chance of showers. Partly sunny, with a high near 82.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Grayslake IL
 42.35°N 88.02°W
Last Update:
1:06 pm CDT Jul 15, 2025
Forecast Valid:
1pm CDT Jul 15, 2025-6pm CDT Jul 21, 2025
 
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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