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Lake Koshkonong, WI Weather & Growing Conditions

Today
83°F
Partly Sunny then Slight Chance Showers And Thunderstorms
A slight chance of showers and thunderstorms after 5pm. Partly sunny, with a high near 83. Southwest wind around 10 mph. Chance of precipitation is 20%.

7-day forecast

WhenTempForecastWindPrecip
Today 83°F Partly Sunny then Slight Chance Showers And Thunderstorms 10 mph SW 17%
Tonight 63°F Chance Showers And Thunderstorms then Showers And Thunderstorms 5 to 10 mph W 92%
Wednesday 75°F Patchy Fog then Chance Showers And Thunderstorms 5 mph NW 68%
Wednesday Night 59°F Chance Showers And Thunderstorms 0 to 5 mph NW 40%
Thursday 79°F Slight Chance Rain Showers then Mostly Sunny 0 to 5 mph N 21%
Thursday Night 58°F Mostly Clear 0 mph 7%
Friday 81°F Mostly Sunny 0 to 5 mph S 2%
Friday Night 62°F Mostly Clear 5 mph SW 5%
Saturday 84°F Mostly Sunny then Slight Chance Showers And Thunderstorms 5 to 10 mph SW 15%
Saturday Night 68°F Slight Chance Showers And Thunderstorms 5 to 10 mph SW 30%
Sunday 85°F Chance Showers And Thunderstorms 10 mph SW 30%
Sunday Night 66°F Chance Showers And Thunderstorms 5 to 10 mph SW 47%
Monday 83°F Chance Rain Showers 5 mph S 46%
Monday Night 66°F Chance Showers And Thunderstorms 5 mph W 44%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Lake Koshkonong, WI

Last spring frost
Apr 28
First fall frost
Oct 13
Growing season
166 days
Hardiness zone
5b

Explore more for Lake Koshkonong, WI: full frost dates · planting calendar · Wisconsin frost dates

Climate data from the nearest NOAA station, Ft Atkinson, Wi (0.7 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.