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Sister Bay, WI Weather & Growing Conditions

Tonight
52°F
Mostly Cloudy then Chance Rain Showers
A chance of rain showers after 1am. Mostly cloudy, with a low around 52. East southeast wind 3 to 7 mph. Chance of precipitation is 30%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
Tonight 52°F Mostly Cloudy then Chance Rain Showers 3 to 7 mph ESE 31%
Saturday 66°F Chance Rain Showers 10 mph ESE 42%
Saturday Night 50°F Chance Rain Showers then Mostly Cloudy 6 to 9 mph NE 39%
Sunday 67°F Partly Sunny 10 to 15 mph NNE 3%
Sunday Night 50°F Mostly Cloudy 10 to 15 mph NE 0%
Monday 63°F Partly Sunny 14 mph ENE 0%
Monday Night 50°F Mostly Cloudy 9 to 13 mph ENE 1%
Tuesday 64°F Mostly Sunny 13 mph ENE 3%
Tuesday Night 49°F Partly Cloudy 6 to 12 mph E 6%
Wednesday 65°F Mostly Sunny 6 to 10 mph ENE 10%
Wednesday Night 50°F Partly Cloudy 3 to 7 mph ENE 6%
Thursday 67°F Mostly Sunny 3 to 7 mph ENE 3%
Thursday Night 51°F Partly Cloudy 3 mph SSW 3%
Friday 70°F Mostly Sunny 6 mph N 4%

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

Growing snapshot for Sister Bay, WI

Last spring frost
May 14
First fall frost
Oct 18
Growing season
155 days
Hardiness zone
5b

Explore more for Sister Bay, WI: full frost dates · planting calendar · Wisconsin frost dates

Climate data from the nearest NOAA station, Ephraim 1Ne-Wwtp, Wi (2.7 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.