What is today's weather forecast for Lanark, IL?

Today's forecast for Lanark shows a low of 13 degrees Fahrenheit. Mostly cloudy, with a low around 13.

What is the 7-day weather forecast for Lanark, IL?

The 7-day forecast for Lanark shows highs from 4 to 39 degrees and lows from -9 to 27 degrees Fahrenheit. Expect precipitation on 3 days with chances of 20% or higher.

Will it rain in Lanark, IL this week?

Yes, rain is possible in Lanark this week. Precipitation chances: Friday (30% chance), Saturday (40% chance), Wednesday (30% chance).

How accurate is the Lanark weather forecast?

WeatherForYou provides highly accurate Lanark forecasts using National Weather Service data and current conditions from the nearest available weather stations, often miles closer than regional airports, for the most precise local forecasts.

Lanark, IL Weather Forecast and Current Conditions

Current Conditions From Nearby Station

Switch to Metric Units

18°F
Feels Like 18°F

Humidity 90% Dew Point 16°F Wind Calm Barometer 30.04 in.

Report from a personal weather station 5.3 mi. N of central Lanark
at 1:31 AM Fri, Dec 12, 2025

Point Forecast at a Glance

ThuDec 11

FriDec 12

30%

SatDec 13

40%

-9

SunDec 14

-9

MonDec 15

TueDec 16

WedDec 17

Jump to detailed forecast ↓

7-Day Temperature Trend

Week Ahead Summary

High temperatures dip from 25°F to a low of 4°F mid-week, then warm to 39°F. Some precipitation possible, including both rain and snow.

Climate Context

This week's forecast shows temperatures running 10°F below the historical average for December. Normal highs for this period are around 34°F with lows around 19°F.

This Date in Weather History

1988 - Arctic cold invaded the central and eastern U.S. Sault Ste Marie MI reported a record low of 14 degrees below zero, and International Falls MN was the cold spot in the nation with a low of 25 degrees below zero. Temperatures remained below zero all day over parts of eastern Upper Michigan and northern New England.

Lanark, IL 7 Day Weather Forecast Details

Thursday Dec 11

Night: Mostly cloudy, with a low around 13. Northeast wind around 5 mph.

Friday Dec 12

Day: A chance of snow or flurries before 3pm, then a chance of flurries between 3pm and 4pm. Mostly cloudy, with a high near 25. Light and variable wind becoming west 5 to 10 mph in the afternoon. Chance of precipitation is 30%.

Night: Mostly cloudy, with a low around 1. Wind chill values as low as -15. West wind 10 to 15 mph, with gusts as high as 20 mph.

Saturday Dec 13

Day: A 40 percent chance of snow. Mostly cloudy and cold, with a high near 7. Wind chill values as low as -15. Northwest wind around 10 mph.

Night: Mostly clear, with a low around -9.

Sunday Dec 14

Day: Sunny and cold, with a high near 4.

Night: Partly cloudy, with a low around -9.

Monday Dec 15

Day: Partly sunny, with a high near 22.

Night: Mostly cloudy, with a low around 11.

Tuesday Dec 16

Day: Partly sunny, with a high near 34.

Night: Mostly cloudy, with a low around 27.

Wednesday Dec 17

Day: Mostly cloudy, with a high near 39.

Night: A 30 percent chance of rain. Mostly cloudy, with a low around 27.

Thursday Dec 18

Day: Partly sunny, with a high near 36.

About Lanark, IL

Lanark is a city in Carroll County, Illinois, United States. The population was 1,504 at the 2020 census. The city was named after Lanark, in Scotland.

Content from Wikipedia, licensed under CC BY-SA 3.0.

How We Provide Better Local Weather

Current conditions: We use the nearest available station to your location - including professional MESONET/MADIS and local weather stations - often miles closer than regional airports.

Forecasts: National Weather Service point forecasts predict for your specific area, not broad regional zones, making them far more relevant to your location.

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