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Hazardous Weather Conditions

Current conditions at

Tri-Township Airport (KSFY)

Lat: 42.05°NLon: 90.11°WElev: 614ft.

Mostly Cloudy

73°F

23°C

Humidity 86%
Wind Speed SE 3 mph
Barometer 29.95 in
Dewpoint 69°F (21°C)
Visibility 10.00 mi
Last update 2 Sep 4:35 am CDT
Extended Forecast for

Lanark IL

Heat Advisory September 2, 04:47am until September 3, 07:00pm
Click here for hazard details and duration
Heat Advisory
  •  
    Heat Advisory September 2, 04:47am until September 3, 07:00pm

    NOW until 7:00pm Thu

    Heat Advisory

  • Today

    High: 92 °F

    Patchy Fog
    then Mostly
    Sunny

  • Tonight

    Tonight: Mostly clear, with a low around 73. Southwest wind around 5 mph.

    Low: 73 °F

    Mostly Clear

  • Thursday

    Thursday: A 40 percent chance of showers and thunderstorms, mainly before 1pm. Mostly sunny, with a high near 89. Calm wind becoming southwest around 5 mph in the morning.

    High: 89 °F

    Chance
    Showers then
    Slight Chance
    T-storms

  • Thursday Night

    Thursday Night: A 30 percent chance of showers and thunderstorms after 1am. Mostly clear, with a low around 72. South wind around 5 mph.

    Low: 72 °F

    Mostly Clear
    then Chance
    T-storms

  • Friday

    Friday: A chance of showers and thunderstorms before 10am, then a chance of showers between 10am and 1pm. Mostly sunny, with a high near 89. Chance of precipitation is 30%.

    High: 89 °F

    Chance
    T-storms then
    Chance
    Showers

  • Friday Night

    Friday Night: A 40 percent chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 70.

    Low: 70 °F

    Partly Cloudy
    then Chance
    T-storms

  • Saturday

    Saturday: Mostly sunny, with a high near 87.

    High: 87 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Partly cloudy, with a low around 68.

    Low: 68 °F

    Partly Cloudy

Detailed Forecast

Today
Patchy fog before 9am. Otherwise, mostly sunny, with a high near 92. Heat index values as high as 101. Southwest wind 5 to 10 mph.
Tonight
Mostly clear, with a low around 73. Southwest wind around 5 mph.
Thursday
A 40 percent chance of showers and thunderstorms, mainly before 1pm. Mostly sunny, with a high near 89. Calm wind becoming southwest around 5 mph in the morning.
Thursday Night
A 30 percent chance of showers and thunderstorms after 1am. Mostly clear, with a low around 72. South wind around 5 mph.
Friday
A chance of showers and thunderstorms before 10am, then a chance of showers between 10am and 1pm. Mostly sunny, with a high near 89. Chance of precipitation is 30%.
Friday Night
A 40 percent chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 70.
Saturday
Mostly sunny, with a high near 87.
Saturday Night
Partly cloudy, with a low around 68.
Sunday
Partly sunny, with a high near 84.
Sunday Night
A 30 percent chance of showers after 1am. Partly cloudy, with a low around 65.
Labor Day
A 30 percent chance of showers. Mostly sunny, with a high near 82.
Monday Night
Mostly cloudy, with a low around 63.
Tuesday
Partly sunny, with a high near 82.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Lanark IL
 42.11°N 89.83°W (Elev. 883 ft)
Last Update:
2:36 am CDT Sep 2, 2026
Forecast Valid:
4am CDT Sep 2, 2026-6pm CDT Sep 8, 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