Lannon, WI Weather & Growing Conditions
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
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| 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). Updated through the day.
Growing snapshot for Lannon, WI
Last spring frost
Apr 30
First fall frost
Oct 16
Growing season
167 days
Hardiness zone
5b
Explore more for Lannon, WI: full frost dates · planting calendar · Wisconsin frost dates
Climate data from the nearest NOAA station, Richfield 3 Ssw, Wi (4.5 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.