Lake-effect Snow and Whiteout Conditions in the Great Lakes Region; Below-average Temperatures in the East

Heavy lake-effect and lake-enhanced snow will persist downwind of the Great Lakes and produce some whiteout conditions that could cause difficult travel conditions. A coastal low will produce moderate to heavy snow over parts of southern and eastern New England into the afternoon. Below average temperatures are expected across the eastern U.S., particularly with chilly morning temperatures. Read More >

Hazardous Weather Conditions

Current conditions at

Sterling Rockfalls (KSQI)

Lat: 41.74°NLon: 89.67°WElev: 643ft.

Fair

2°F

-17°C

Humidity 80%
Wind Speed Calm
Barometer 30.38 in (1030.3 mb)
Dewpoint -3°F (-19°C)
Visibility 10.00 mi
Last update 20 Jan 7:56 am CST
Extended Forecast for

Lanark IL

  • Today

    Today: Increasing clouds, with a high near 21. Wind chill values as low as -10. Southwest wind 5 to 10 mph.

    High: 21 °F

    Increasing
    Clouds

  • Tonight

    Tonight: Snow, mainly after 9pm.  Temperature rising to around 23 by 1am. South wind 5 to 10 mph becoming west after midnight.  Chance of precipitation is 80%. New snow accumulation of 2 to 4 inches possible.

    Low: 17 °F

    Snow

  • Wednesday

    Wednesday: Patchy blowing snow after 4pm. Partly sunny, with a high near 27. West wind 10 to 15 mph, with gusts as high as 25 mph.

    High: 27 °F

    Partly Sunny
    then Patchy
    Blowing Snow

  • Wednesday Night

    Wednesday Night: A 50 percent chance of snow showers before midnight.  Patchy blowing snow before midnight. Mostly cloudy, then gradually becoming mostly clear, with a low around 7. Wind chill values as low as -5. West wind 10 to 15 mph, with gusts as high as 30 mph.  New snow accumulation of less than one inch possible.

    Low: 7 °F

    Chance Snow
    Showers and
    Patchy
    Blowing Snow

  • Thursday

    Thursday: Mostly sunny, with a high near 18.

    High: 18 °F

    Mostly Sunny

  • Thursday Night

    Thursday Night: Partly cloudy, with a low around -12.

    Low: -12 °F

    Partly Cloudy

  • Friday

    Friday: Mostly sunny and cold, with a high near -3.

    High: -3 °F

    Cold

  • Friday Night

    Friday Night: Partly cloudy, with a low around -13.

    Low: -13 °F

    Partly Cloudy

  • Saturday

    Saturday: Partly sunny and cold, with a high near 2.

    High: 2 °F

    Cold

Detailed Forecast

Today
Increasing clouds, with a high near 21. Wind chill values as low as -10. Southwest wind 5 to 10 mph.
Tonight
Snow, mainly after 9pm. Temperature rising to around 23 by 1am. South wind 5 to 10 mph becoming west after midnight. Chance of precipitation is 80%. New snow accumulation of 2 to 4 inches possible.
Wednesday
Patchy blowing snow after 4pm. Partly sunny, with a high near 27. West wind 10 to 15 mph, with gusts as high as 25 mph.
Wednesday Night
A 50 percent chance of snow showers before midnight. Patchy blowing snow before midnight. Mostly cloudy, then gradually becoming mostly clear, with a low around 7. Wind chill values as low as -5. West wind 10 to 15 mph, with gusts as high as 30 mph. New snow accumulation of less than one inch possible.
Thursday
Mostly sunny, with a high near 18.
Thursday Night
Partly cloudy, with a low around -12.
Friday
Mostly sunny and cold, with a high near -3.
Friday Night
Partly cloudy, with a low around -13.
Saturday
Partly sunny and cold, with a high near 2.
Saturday Night
Mostly cloudy, with a low around -7.
Sunday
Mostly sunny, with a high near 14.
Sunday Night
Partly cloudy, with a low around -3.
Monday
Sunny, with a high near 15.
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ABOUT THIS FORECAST

 
Point Forecast:
Lanark IL
 42.11°N 89.83°W (Elev. 883 ft)
5:16 am CST Jan 20, 2026
8am CST Jan 20, 2026-6pm CST Jan 26, 2026
 
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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