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

Sterling Rockfalls (KSQI)

Lat: 41.74°NLon: 89.67°WElev: 643ft.

Fair

80°F

27°C

Humidity 79%
Wind Speed Calm
Barometer 29.95 in (1013.6 mb)
Dewpoint 73°F (23°C)
Visibility 10.00 mi
Heat Index84°F (29°C)
Last update 1 Sep 10:56 pm CDT
Extended Forecast for

Harmon IL

  • Tonight

    Tonight: Mostly clear, with a low around 72. South wind around 5 mph, with gusts as high as 10 mph.

    Low: 72 °F

    Mostly Clear

  • Wednesday

    Wednesday: Sunny, with a high near 94. Heat index values as high as 102. Southwest wind 5 to 15 mph, with gusts as high as 20 mph.

    High: 94 °F

    Sunny

  • Wednesday Night

    Wednesday Night: Mostly clear, with a low around 73. South southwest wind around 5 mph, with gusts as high as 10 mph.

    Low: 73 °F

    Mostly Clear

  • Thursday

    Thursday: A slight chance of showers, with thunderstorms also possible after 10am. Mostly sunny, with a high near 91. Heat index values as high as 100. South wind around 5 mph, with gusts as high as 10 mph. Chance of precipitation is 20%.

    High: 91 °F

    Slight Chance
    T-storms

  • Thursday Night

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

    Low: 72 °F

    Chance
    T-storms

  • Friday

    Friday: A 40 percent chance of showers and thunderstorms before 1pm. Mostly sunny, with a high near 90.

    High: 90 °F

    Chance
    T-storms

  • Friday Night

    Friday Night: A 30 percent chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 71.

    Low: 71 °F

    Partly Cloudy
    then Chance
    T-storms

  • Saturday

    Saturday: Mostly sunny, with a high near 88.

    High: 88 °F

    Mostly Sunny

  • Saturday Night

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

    Low: 68 °F

    Partly Cloudy

Detailed Forecast

Tonight
Mostly clear, with a low around 72. South wind around 5 mph, with gusts as high as 10 mph.
Wednesday
Sunny, with a high near 94. Heat index values as high as 102. Southwest wind 5 to 15 mph, with gusts as high as 20 mph.
Wednesday Night
Mostly clear, with a low around 73. South southwest wind around 5 mph, with gusts as high as 10 mph.
Thursday
A slight chance of showers, with thunderstorms also possible after 10am. Mostly sunny, with a high near 91. Heat index values as high as 100. South wind around 5 mph, with gusts as high as 10 mph. Chance of precipitation is 20%.
Thursday Night
A 30 percent chance of showers and thunderstorms, mainly after 1am. Partly cloudy, with a low around 72. South southeast wind around 5 mph.
Friday
A 40 percent chance of showers and thunderstorms before 1pm. Mostly sunny, with a high near 90.
Friday Night
A 30 percent chance of showers and thunderstorms after 1am. Partly cloudy, with a low around 71.
Saturday
Mostly sunny, with a high near 88.
Saturday Night
Partly cloudy, with a low around 68.
Sunday
Partly sunny, with a high near 85.
Sunday Night
Partly cloudy, with a low around 65.
Labor Day
Mostly sunny, with a high near 82.
Monday Night
Mostly cloudy, with a low around 62.
Tuesday
Partly sunny, with a high near 81.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Harmon IL
 41.73°N 89.56°W
Last Update:
9:06 pm CDT Sep 1, 2026
Forecast Valid:
11pm CDT Sep 1, 2026-6pm CDT Sep 8, 2026
 
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Additional Resources

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Hourly Weather Forecast

National Digital Forecast Database

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High Temperature

National Digital Forecast Database Weather Element Forecast

Chance of Precipitation