Sullivan, WI Weather & Growing Conditions
Tonight
58°F
Light Rain
Rain. Cloudy, with a low around 58. South wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 80%. New rainfall amounts between a quarter and half of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 58°F | Light Rain | 10 to 15 mph S | 84% |
| Wednesday | 60°F | Chance Light Rain | 10 to 15 mph S | 26% |
| Wednesday Night | 46°F | Cloudy then Slight Chance Light Rain | 15 mph SW | 22% |
| Thursday | 53°F | Chance Light Rain | 10 to 15 mph W | 54% |
| Thursday Night | 39°F | Chance Light Rain | 5 to 10 mph NW | 52% |
| Friday | 49°F | Slight Chance Light Rain then Mostly Cloudy | 5 to 15 mph N | 20% |
| Friday Night | 31°F | Partly Cloudy | 0 to 5 mph N | 2% |
| Saturday | 52°F | Mostly Sunny | 0 to 5 mph W | 4% |
| Saturday Night | 32°F | Partly Cloudy | 0 to 5 mph W | 8% |
| Sunday | 57°F | Slight Chance Light Rain | 5 to 10 mph W | 17% |
| Sunday Night | 34°F | Mostly Clear | 5 mph W | 5% |
| Monday | 59°F | Mostly Sunny | 5 to 10 mph SW | 1% |
| Monday Night | 38°F | Mostly Clear | 5 to 10 mph W | 1% |
| Tuesday | 59°F | Mostly Sunny | 5 to 10 mph W | 0% |
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 Nov 4, 2026.