Sullivan, WI Weather & Growing Conditions
Tonight
60°F
Showers And Thunderstorms
A chance of rain showers before 10pm, then showers and thunderstorms. Some of the storms could produce heavy rain. Cloudy, with a low around 60. East wind 10 to 15 mph. Chance of precipitation is 100%. New rainfall amounts between 1 and 2 inches possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 60°F | Showers And Thunderstorms | 10 to 15 mph E | 95% |
| Saturday | 72°F | Showers And Thunderstorms | 10 to 15 mph SE | 94% |
| Saturday Night | 59°F | Showers And Thunderstorms Likely | 5 to 10 mph E | 73% |
| Sunday | 67°F | Chance Rain Showers | 10 to 15 mph NE | 42% |
| Sunday Night | 53°F | Slight Chance Rain Showers then Mostly Cloudy | 10 to 15 mph NE | 24% |
| Monday | 63°F | Slight Chance Rain Showers | 10 to 15 mph NE | 16% |
| Monday Night | 48°F | Mostly Cloudy | 5 to 10 mph NE | 14% |
| Tuesday | 62°F | Partly Sunny | 10 to 15 mph NE | 14% |
| Tuesday Night | 47°F | Partly Cloudy | 5 to 10 mph NE | 8% |
| Wednesday | 65°F | Partly Sunny | 5 to 10 mph NE | 8% |
| Wednesday Night | 48°F | Partly Cloudy | 0 to 5 mph NE | 4% |
| Thursday | 67°F | Partly Sunny | 0 to 5 mph NE | 3% |
| Thursday Night | 50°F | Partly Cloudy | 0 to 5 mph NE | 4% |
| Friday | 70°F | Mostly Sunny | 0 to 5 mph N | 4% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Sullivan, WI
Last spring frost
May 3
First fall frost
Oct 9
Growing season
157 days
Hardiness zone
5b
Explore more for Sullivan, WI: full frost dates · planting calendar · Wisconsin frost dates
Climate data from the nearest NOAA station, Sullivan 3Se, Wi (4.9 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.