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

Hazardous Weather Conditions

Current conditions at

Tri-Township Airport (KSFY)

Lat: 42.05°NLon: 90.11°WElev: 614ft.

Light Rain

73°F

23°C

Humidity 96%
Wind Speed E 9 mph
Barometer 29.93 in
Dewpoint 72°F (22°C)
Visibility 4.00 mi
Last update 13 Aug 12:55 pm CDT
Extended Forecast for

Lanark IL

Flood Watch August 13, 07:00pm until August 14, 01:00pm
Click here for hazard details and duration
Flood Watch

  • This Afternoon

    This Afternoon: Occasional showers and thunderstorms, mainly before 3pm. High near 77. East wind around 10 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.

    High: 77 °F

    T-storms

  • Tonight

    Tonight: Occasional showers and thunderstorms. Low around 64. East wind around 10 mph. Chance of precipitation is 80%. New rainfall amounts between 1 and 2 inches possible.

    Low: 64 °F

    Chance
    T-storms then
    T-storms

  • Friday

    Friday: Showers and thunderstorms likely, mainly before 2pm. Mostly cloudy, with a high near 79. East wind around 10 mph. Chance of precipitation is 60%.

    High: 79 °F

    T-storms
    Likely

  • Friday Night

    Friday Night: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 67. East wind around 10 mph. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 67 °F

    Chance
    T-storms then
    Showers
    Likely

  • Saturday

    Saturday: Showers likely and possibly a thunderstorm before 10am, then showers likely between 10am and 1pm. Mostly cloudy, with a high near 85. Chance of precipitation is 60%. New precipitation amounts between a quarter and half of an inch possible.

    High: 85 °F

    Showers
    Likely

  • Saturday Night

    Saturday Night: A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 70. Chance of precipitation is 60%.

    Low: 70 °F

    Chance
    T-storms then
    Showers
    Likely

  • Sunday

    Sunday: Mostly cloudy, with a high near 82.

    High: 82 °F

    Mostly Cloudy

  • Sunday Night

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

    Low: 63 °F

    Partly Cloudy

  • Monday

    Monday: Mostly sunny, with a high near 78.

    High: 78 °F

    Mostly Sunny

Detailed Forecast

This Afternoon
Occasional showers and thunderstorms, mainly before 3pm. High near 77. East wind around 10 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.
Tonight
Occasional showers and thunderstorms. Low around 64. East wind around 10 mph. Chance of precipitation is 80%. New rainfall amounts between 1 and 2 inches possible.
Friday
Showers and thunderstorms likely, mainly before 2pm. Mostly cloudy, with a high near 79. East wind around 10 mph. Chance of precipitation is 60%.
Friday Night
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 67. East wind around 10 mph. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible.
Saturday
Showers likely and possibly a thunderstorm before 10am, then showers likely between 10am and 1pm. Mostly cloudy, with a high near 85. Chance of precipitation is 60%. New precipitation amounts between a quarter and half of an inch possible.
Saturday Night
A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 1am. Mostly cloudy, with a low around 70. Chance of precipitation is 60%.
Sunday
Mostly cloudy, with a high near 82.
Sunday Night
Partly cloudy, with a low around 63.
Monday
Mostly sunny, with a high near 78.
Monday Night
Mostly clear, with a low around 59.
Tuesday
Mostly sunny, with a high near 79.
Tuesday Night
A 30 percent chance of showers. Partly cloudy, with a low around 62.
Wednesday
A 30 percent chance of showers. Partly sunny, with a high near 79.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Lanark IL
 42.11°N 89.83°W (Elev. 883 ft)
Last Update:
10:51 am CDT Aug 13, 2026
Forecast Valid:
1pm CDT Aug 13, 2026-6pm CDT Aug 19, 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