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

Hazardous Weather Conditions

Current conditions at

Chicago/Waukegan Regional Airport (KUGN)

Lat: 42.43°NLon: 87.86°WElev: 709ft.

Fair

92°F

33°C

Humidity 60%
Wind Speed SW 13 G 25 mph
Barometer 29.88 in (1010.2 mb)
Dewpoint 76°F (24°C)
Visibility 10.00 mi
Heat Index105°F (41°C)
Last update 29 Jun 2:51 pm CDT
Extended Forecast for

McHenry IL

Heat Advisory until July 1, 10:00pm
Click here for hazard details and duration
Heat Advisory
  •  
    Heat Advisory until July 1, 10:00pm

    NOW until 10:00pm Wed

    Heat Advisory

  • This Afternoon

    High: 91 °F

    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 77. South southwest wind 10 to 15 mph, with gusts as high as 20 mph.

    Low: 77 °F

    Mostly Clear

  • Tuesday

    Tuesday: Sunny, with a high near 93. Heat index values as high as 108. Southwest wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 93 °F

    Sunny

  • Tuesday Night

    Tuesday Night: Mostly clear, with a low around 77. Southwest wind 10 to 15 mph, with gusts as high as 25 mph.

    Low: 77 °F

    Mostly Clear

  • Wednesday

    Wednesday: Sunny and hot, with a high near 95. Southwest wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 95 °F

    Hot

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 77.

    Low: 77 °F

    Mostly Clear

  • Thursday

    Thursday: Mostly sunny, with a high near 92.

    High: 92 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Partly cloudy, with a low around 74.

    Low: 74 °F

    Chance
    T-storms then
    Showers
    Likely

Detailed Forecast

This Afternoon
Sunny, with a high near 91. Heat index values as high as 103. South southwest wind around 15 mph, with gusts as high as 25 mph.
Tonight
Mostly clear, with a low around 77. South southwest wind 10 to 15 mph, with gusts as high as 20 mph.
Tuesday
Sunny, with a high near 93. Heat index values as high as 108. Southwest wind 10 to 15 mph, with gusts as high as 25 mph.
Tuesday Night
Mostly clear, with a low around 77. Southwest wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday
Sunny and hot, with a high near 95. Southwest wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday Night
Mostly clear, with a low around 77.
Thursday
Mostly sunny, with a high near 92.
Thursday Night
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Partly cloudy, with a low around 74.
Friday
A chance of showers and thunderstorms. Partly sunny, with a high near 89.
Friday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 71.
Independence Day
A chance of showers and thunderstorms. Mostly sunny, with a high near 87.
Saturday Night
A chance of showers and thunderstorms. Partly cloudy, with a low around 69.
Sunday
A chance of showers and thunderstorms. Partly sunny, with a high near 85.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
McHenry IL
 42.34°N 88.26°W
Last Update:
1:21 pm CDT Jun 29, 2026
Forecast Valid:
3pm CDT Jun 29, 2026-6pm CDT Jul 5, 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