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

19°F

-7°C

Humidity 77%
Wind Speed Calm
Barometer 30.35 in (1029.8 mb)
Dewpoint 13°F (-11°C)
Visibility 10.00 mi
Last update 23 Feb 6:51 pm CST
Extended Forecast for

McHenry IL

  • Tonight

    Tonight: Increasing clouds, with a low around 16. Light and variable wind becoming south 5 to 10 mph after midnight.

    Low: 16 °F

    Increasing
    Clouds

  • Tuesday

    Tuesday: A slight chance of snow showers between 3pm and 4pm, then a slight chance of rain showers after 4pm. Cloudy, with a high near 41. Breezy, with a south wind 10 to 15 mph increasing to 20 to 25 mph in the afternoon. Winds could gust as high as 40 mph. Chance of precipitation is 20%.

    High: 41 °F

    Breezy.
    Mostly Cloudy
    then Slight
    Chance
    Rain/Snow

  • Tuesday Night

    Tuesday Night: Cloudy, then gradually becoming partly cloudy, with a low around 21. West northwest wind around 15 mph, with gusts as high as 25 mph.

    Low: 21 °F

    Decreasing
    Clouds

  • Wednesday

    Wednesday: Sunny, with a high near 32. West northwest wind 5 to 15 mph, with gusts as high as 20 mph.

    High: 32 °F

    Sunny

  • Wednesday Night

    Wednesday Night: A 40 percent chance of snow, mainly after midnight. Mostly cloudy, with a low around 20. West northwest wind around 5 mph becoming northeast after midnight. Winds could gust as high as 15 mph.

    Low: 20 °F

    Chance Snow

  • Thursday

    Thursday: A 20 percent chance of snow before noon. Mostly sunny, with a high near 40.

    High: 40 °F

    Slight Chance
    Snow then
    Mostly Sunny

  • Thursday Night

    Thursday Night: Mostly clear, with a low around 26.

    Low: 26 °F

    Mostly Clear

  • Friday

    Friday: Mostly sunny, with a high near 54.

    High: 54 °F

    Mostly Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 29.

    Low: 29 °F

    Partly Cloudy

Detailed Forecast

Tonight
Increasing clouds, with a low around 16. Light and variable wind becoming south 5 to 10 mph after midnight.
Tuesday
A slight chance of snow showers between 3pm and 4pm, then a slight chance of rain showers after 4pm. Cloudy, with a high near 41. Breezy, with a south wind 10 to 15 mph increasing to 20 to 25 mph in the afternoon. Winds could gust as high as 40 mph. Chance of precipitation is 20%.
Tuesday Night
Cloudy, then gradually becoming partly cloudy, with a low around 21. West northwest wind around 15 mph, with gusts as high as 25 mph.
Wednesday
Sunny, with a high near 32. West northwest wind 5 to 15 mph, with gusts as high as 20 mph.
Wednesday Night
A 40 percent chance of snow, mainly after midnight. Mostly cloudy, with a low around 20. West northwest wind around 5 mph becoming northeast after midnight. Winds could gust as high as 15 mph.
Thursday
A 20 percent chance of snow before noon. Mostly sunny, with a high near 40.
Thursday Night
Mostly clear, with a low around 26.
Friday
Mostly sunny, with a high near 54.
Friday Night
Partly cloudy, with a low around 29.
Saturday
Partly sunny, with a high near 40.
Saturday Night
Mostly cloudy, with a low around 18.
Sunday
A chance of snow. Partly sunny, with a high near 30.
Sunday Night
A chance of snow. Mostly cloudy, with a low around 19.
Monday
Mostly cloudy, with a high near 32.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
McHenry IL
 42.34°N 88.26°W
Last Update:
4:46 pm CST Feb 23, 2026
Forecast Valid:
7pm CST Feb 23, 2026-6pm CST Mar 2, 2026
 
Forecast Discussion
 
Get as KML Get as XML

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