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Lannon, WI Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Lannon, a village in Waukesha County, Wisconsin.

Today
67°F
Showers And Thunderstorms
Showers and thunderstorms before 1pm, then a chance of showers and thunderstorms between 1pm and 2pm, then showers and thunderstorms. Cloudy, with a high near 67. East wind 5 to 10 mph. Chance of precipitation is 80%. New rainfall amounts between a half and three quarters of an inch possible.

7-day forecast for Lannon

WhenTempForecastWindPrecip
Today 67°F Showers And Thunderstorms 5 to 10 mph E 78%
Tonight 59°F Showers And Thunderstorms 5 to 10 mph NE 84%
Sunday 64°F Chance Rain Showers then Cloudy 10 to 15 mph NE 41%
Sunday Night 53°F Mostly Cloudy 10 to 15 mph NE 2%
Monday 61°F Mostly Cloudy 10 to 15 mph NE 5%
Monday Night 50°F Mostly Cloudy 5 to 15 mph NE 5%
Tuesday 61°F Partly Sunny 5 to 15 mph NE 7%
Tuesday Night 49°F Partly Cloudy 5 to 10 mph NE 6%
Wednesday 63°F Mostly Sunny 5 to 10 mph NE 6%
Wednesday Night 51°F Partly Cloudy 0 to 5 mph NE 2%
Thursday 65°F Mostly Sunny 5 to 10 mph NE 4%
Thursday Night 51°F Partly Cloudy 0 to 5 mph NE 3%
Friday 69°F Mostly Sunny 0 to 5 mph NE 4%
Friday Night 52°F Partly Cloudy 0 to 5 mph NE 3%

Forecast source: National Weather Service (api.weather.gov) for Lannon (43.157, -88.158). Updated through the day.

Growing snapshot for Lannon

Last spring frost
Apr 30
First fall frost
Oct 16
Growing season
167 days
Hardiness zone
5b

More local growing data for Lannon: nearby ZIP 53046 weather · frost dates · planting calendar · Wisconsin frost dates

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Climate data from the nearest NOAA station, Richfield 3 Ssw, Wi (4.5 mi from Lannon). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.