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Hazardous Weather Conditions

Current conditions at

Janesville-Rock County (KJVL)

Lat: 42.62°NLon: 89.04°WElev: 801ft.

Fog/Mist

66°F

19°C

Humidity 100%
Wind Speed Calm
Barometer 29.91 in
Dewpoint 66°F (19°C)
Visibility 1.50 mi
Last update 13 Aug 4:55 am CDT
Extended Forecast for

Janesville WI

Dense Fog Advisory until August 13, 09:00am
Click here for hazard details and duration
Dense Fog Advisory
  •  
    Dense Fog Advisory until August 13, 09:00am

    NOW until 9:00am Thu

    Dense Fog Advisory

  • Overnight

    Low: 65 °F

    Patchy Fog

  • Thursday

    Thursday: A chance of showers before 1pm, then showers likely and possibly a thunderstorm between 1pm and 3pm, then a chance of showers and thunderstorms after 3pm. Patchy fog before 9am. Otherwise, mostly cloudy, with a high near 77. Calm wind becoming east around 5 mph in the afternoon. Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    High: 77 °F

    Chance
    Showers and
    Patchy Fog
    then Showers
    Likely

  • Thursday Night

    Thursday Night: A chance of showers before midnight, then a chance of showers after 1am. Mostly cloudy, with a low around 63. East wind around 5 mph. Chance of precipitation is 30%.

    Low: 63 °F

    Chance
    Showers

  • Friday

    Friday: A chance of showers before 11am, then a chance of showers after 3pm. Mostly cloudy, with a high near 78. East wind 5 to 10 mph. Chance of precipitation is 40%.

    High: 78 °F

    Chance
    Showers

  • Friday Night

    Friday Night: A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 1am. Low around 65. East wind 5 to 10 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.

    Low: 65 °F

    Chance
    T-storms then
    Showers

  • Saturday

    Saturday: Showers likely and possibly a thunderstorm before 1pm, then a chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 82. Southeast wind 5 to 10 mph becoming southwest in the afternoon. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible.

    High: 82 °F

    Showers
    Likely

  • Saturday Night

    Saturday Night: Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 69. Southwest wind around 5 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.

    Low: 69 °F

    Showers
    Likely

  • Sunday

    Sunday: A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 81. Northwest wind 5 to 10 mph.

    High: 81 °F

    Chance
    T-storms

Detailed Forecast

Overnight
Patchy fog. Otherwise, mostly cloudy, with a low around 65. Calm wind.
Thursday
A chance of showers before 1pm, then showers likely and possibly a thunderstorm between 1pm and 3pm, then a chance of showers and thunderstorms after 3pm. Patchy fog before 9am. Otherwise, mostly cloudy, with a high near 77. Calm wind becoming east around 5 mph in the afternoon. Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Thursday Night
A chance of showers before midnight, then a chance of showers after 1am. Mostly cloudy, with a low around 63. East wind around 5 mph. Chance of precipitation is 30%.
Friday
A chance of showers before 11am, then a chance of showers after 3pm. Mostly cloudy, with a high near 78. East wind 5 to 10 mph. Chance of precipitation is 40%.
Friday Night
A chance of showers and thunderstorms, then showers and possibly a thunderstorm after 1am. Low around 65. East wind 5 to 10 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
Saturday
Showers likely and possibly a thunderstorm before 1pm, then a chance of showers and thunderstorms after 1pm. Mostly cloudy, with a high near 82. Southeast wind 5 to 10 mph becoming southwest in the afternoon. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible.
Saturday Night
Showers likely and possibly a thunderstorm. Mostly cloudy, with a low around 69. Southwest wind around 5 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch, except higher amounts possible in thunderstorms.
Sunday
A 30 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 81. Northwest wind 5 to 10 mph.
Sunday Night
Partly cloudy, with a low around 62.
Monday
Mostly sunny, with a high near 77.
Monday Night
Mostly clear, with a low around 58.
Tuesday
Mostly sunny, with a high near 77.
Tuesday Night
A 40 percent chance of showers and thunderstorms. Partly cloudy, with a low around 62.
Wednesday
A 40 percent chance of showers and thunderstorms. Mostly cloudy, with a high near 77.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Janesville WI
 42.69°N 89.01°W (Elev. 863 ft)
Last Update:
2:47 am CDT Aug 13, 2026
Forecast Valid:
5am 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