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

Janesville-Rock County (KJVL)

Lat: 42.62°NLon: 89.04°WElev: 801ft.

Fair

66°F

19°C

Humidity 88%
Wind Speed NW 3 mph
Barometer 30.07 in
Dewpoint 63°F (17°C)
Visibility 10.00 mi
Last update 20 Aug 8:45 am CDT
Extended Forecast for

South Beloit IL

  • Today

    Today: Sunny, with a high near 80. Calm wind.

    High: 80 °F

    Sunny

  • Tonight

    Tonight: Partly cloudy, with a low around 59. Southeast wind around 5 mph.

    Low: 59 °F

    Partly Cloudy

  • Friday

    Friday: A chance of showers before 1pm, then a chance of showers and thunderstorms after 3pm. Partly sunny, with a high near 80. Southwest wind 5 to 10 mph. Chance of precipitation is 40%.

    High: 80 °F

    Chance
    Showers then
    Chance
    T-storms

  • Friday Night

    Friday Night: A chance of showers and thunderstorms before 10pm, then a slight chance of showers between 10pm and 1am. Partly cloudy, with a low around 59. Southwest wind around 5 mph becoming northwest after midnight. Chance of precipitation is 30%.

    Low: 59 °F

    Chance
    T-storms then
    Slight Chance
    Showers

  • Saturday

    Saturday: Sunny, with a high near 78. Northwest wind 5 to 10 mph.

    High: 78 °F

    Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 54. Northwest wind around 5 mph becoming calm in the evening.

    Low: 54 °F

    Mostly Clear

  • Sunday

    Sunday: Sunny, with a high near 75. Light north wind increasing to 5 to 10 mph in the morning.

    High: 75 °F

    Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 53. Calm wind.

    Low: 53 °F

    Partly Cloudy

  • Monday

    Monday: Mostly sunny, with a high near 76.

    High: 76 °F

    Mostly Sunny

Detailed Forecast

Today
Sunny, with a high near 80. Calm wind.
Tonight
Partly cloudy, with a low around 59. Southeast wind around 5 mph.
Friday
A chance of showers before 1pm, then a chance of showers and thunderstorms after 3pm. Partly sunny, with a high near 80. Southwest wind 5 to 10 mph. Chance of precipitation is 40%.
Friday Night
A chance of showers and thunderstorms before 10pm, then a slight chance of showers between 10pm and 1am. Partly cloudy, with a low around 59. Southwest wind around 5 mph becoming northwest after midnight. Chance of precipitation is 30%.
Saturday
Sunny, with a high near 78. Northwest wind 5 to 10 mph.
Saturday Night
Mostly clear, with a low around 54. Northwest wind around 5 mph becoming calm in the evening.
Sunday
Sunny, with a high near 75. Light north wind increasing to 5 to 10 mph in the morning.
Sunday Night
Partly cloudy, with a low around 53. Calm wind.
Monday
Mostly sunny, with a high near 76.
Monday Night
Partly cloudy, with a low around 56.
Tuesday
Mostly sunny, with a high near 79.
Tuesday Night
A 30 percent chance of showers and thunderstorms. Partly cloudy, with a low around 61.
Wednesday
A 20 percent chance of showers and thunderstorms. Mostly sunny, with a high near 80.
Basemap Options
Click map to change the forecast location
Loading map...
Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
South Beloit IL
 42.49°N 89.02°W (Elev. 732 ft)
Last Update:
8:36 am CDT Aug 20, 2026
Forecast Valid:
8am CDT Aug 20, 2026-6pm CDT Aug 26, 2026
 
Forecast Discussion
 
Get as KML Get as XML

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