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Hazardous Weather Conditions

Current conditions at

Janesville-Rock County (KJVL)

Lat: 42.62°NLon: 89.04°WElev: 801ft.

Freezing Fog

27°F

-3°C

Humidity 100%
Wind Speed Calm
Barometer 30.20 in
Dewpoint 27°F (-3°C)
Visibility 0.25 mi
Last update 4 Mar 6:45 am CST
Extended Forecast for

Harvard IL

Dense Fog Advisory March 4, 07:10am until March 4, 09:00am
Click here for hazard details and duration
...
  •  
    Dense Fog Advisory March 4, 07:10am until March 4, 09:00am

    NOW until 9:00am Wed

    Dense Fog Advisory

  • Today

    High: 47 °F

    Dense Fog
    then Mostly
    Cloudy

  • Tonight

    Tonight: A slight chance of showers or drizzle between 11pm and midnight, then a chance of showers after midnight. Patchy fog after 9pm. Otherwise, cloudy, with a low around 40. East wind around 5 mph. Chance of precipitation is 50%.

    Low: 40 °F

    Chance
    Showers and
    Patchy Fog

  • Thursday

    Thursday: Showers likely, mainly before noon. Areas of fog. Otherwise, cloudy, with a high near 47. East northeast wind 5 to 10 mph. Chance of precipitation is 70%. New precipitation amounts between a tenth and quarter of an inch possible.

    High: 47 °F

    Showers
    Likely and
    Areas Fog

  • Thursday Night

    Thursday Night: A 20 percent chance of showers after 3am. Patchy fog. Otherwise, mostly cloudy, with a low around 41. Southeast wind around 5 mph.

    Low: 41 °F

    Patchy Fog
    then Slight
    Chance
    Showers and
    Patchy Fog

  • Friday

    Friday: A chance of showers and thunderstorms before 9am, then showers and possibly a thunderstorm between 9am and 3pm, then a chance of showers and thunderstorms after 3pm. Patchy fog before noon. High near 68. Southeast wind 10 to 15 mph becoming south southwest in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 90%.

    High: 68 °F

    Showers and
    Patchy Fog

  • Friday Night

    Friday Night: A chance of showers, then showers and possibly a thunderstorm after 9pm. Low around 46. Chance of precipitation is 90%.

    Low: 46 °F

    Showers

  • Saturday

    Saturday: A 20 percent chance of showers before noon. Partly sunny, with a high near 55.

    High: 55 °F

    Slight Chance
    Showers then
    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 34.

    Low: 34 °F

    Mostly Clear

Detailed Forecast

Today
Widespread dense fog, mainly before 8am. Otherwise, partly sunny, with a high near 47. East wind 5 to 10 mph.
Tonight
A slight chance of showers or drizzle between 11pm and midnight, then a chance of showers after midnight. Patchy fog after 9pm. Otherwise, cloudy, with a low around 40. East wind around 5 mph. Chance of precipitation is 50%.
Thursday
Showers likely, mainly before noon. Areas of fog. Otherwise, cloudy, with a high near 47. East northeast wind 5 to 10 mph. Chance of precipitation is 70%. New precipitation amounts between a tenth and quarter of an inch possible.
Thursday Night
A 20 percent chance of showers after 3am. Patchy fog. Otherwise, mostly cloudy, with a low around 41. Southeast wind around 5 mph.
Friday
A chance of showers and thunderstorms before 9am, then showers and possibly a thunderstorm between 9am and 3pm, then a chance of showers and thunderstorms after 3pm. Patchy fog before noon. High near 68. Southeast wind 10 to 15 mph becoming south southwest in the afternoon. Winds could gust as high as 25 mph. Chance of precipitation is 90%.
Friday Night
A chance of showers, then showers and possibly a thunderstorm after 9pm. Low around 46. Chance of precipitation is 90%.
Saturday
A 20 percent chance of showers before noon. Partly sunny, with a high near 55.
Saturday Night
Mostly clear, with a low around 34.
Sunday
Mostly sunny, with a high near 59. Breezy.
Sunday Night
Mostly clear, with a low around 41.
Monday
Sunny, with a high near 68.
Monday Night
Mostly clear, with a low around 49.
Tuesday
Showers likely. Partly sunny, with a high near 67. Breezy.
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Forecast Area
Tiles ©ESRI

ABOUT THIS FORECAST

 
Point Forecast:
Harvard IL
 42.42°N 88.61°W
Last Update:
6:56 am CST Mar 4, 2026
Forecast Valid:
7am CST Mar 4, 2026-6pm CDT Mar 10, 2026
 
Forecast Discussion
 
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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