NWS Forecast for Janesville WI

National Weather Service Forecast for: Janesville WI
Issued by: National Weather Service Milwaukee, WI

Updated: 5:13 am CST Feb 2, 2026

Overnight Slight Chance Wintry Mix	Monday Chance Flurries	Monday Night Slight Chance Snow	Tuesday Sunny	Tuesday Night Mostly Clear	Wednesday Sunny	Wednesday Night Partly Cloudy	Thursday Partly Sunny	Thursday Night Chance Snow
Lo 18 °F	Hi 24 °F	Lo 10 °F	Hi 20 °F	Lo 2 °F	Hi 23 °F	Lo 9 °F	Hi 31 °F	Lo 29 °F

Hazardous Weather Outlook

Overnight	A slight chance of snow and freezing rain. Cloudy, with a low around 18. West wind around 5 mph. Chance of precipitation is 20%.
Monday	A chance of flurries before 11am. Mostly cloudy, with a high near 24. Northwest wind 5 to 10 mph.
Monday Night	A slight chance of snow between 10pm and 2am. Mostly cloudy, with a low around 10. West wind around 5 mph becoming calm. Chance of precipitation is 20%.
Tuesday	Sunny, with a high near 20. North wind around 5 mph.
Tuesday Night	Mostly clear, with a low around 2. North wind around 5 mph becoming calm.
Wednesday	Sunny, with a high near 23. Calm wind becoming west around 5 mph.
Wednesday Night	Partly cloudy, with a low around 9. West wind around 5 mph becoming calm.
Thursday	Partly sunny, with a high near 31. Southwest wind 5 to 10 mph.
Thursday Night	A 30 percent chance of snow, mainly before midnight. Mostly cloudy, with a low around 29.
Friday	A 20 percent chance of snow before noon. Partly sunny, with a high near 33.
Friday Night	Partly cloudy, with a low around 7.
Saturday	Mostly sunny, with a high near 23.
Saturday Night	Partly cloudy, with a low around 14.
Sunday	Mostly sunny, with a high near 27.

Forecast from NOAA-NWS for Janesville WI.