Sullivan, WI Weather & Growing Conditions
Today
83°F
Partly Sunny
Partly sunny, with a high near 83. Southwest wind around 10 mph.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 83°F | Partly Sunny | 10 mph SW | 14% |
| Tonight | 64°F | Chance Showers And Thunderstorms then Showers And Thunderstorms | 0 to 10 mph W | 91% |
| Wednesday | 75°F | Patchy Fog then Chance Showers And Thunderstorms | 5 mph W | 68% |
| Wednesday Night | 59°F | Chance Showers And Thunderstorms | 0 to 5 mph NW | 39% |
| Thursday | 78°F | Slight Chance Rain Showers then Mostly Sunny | 0 to 5 mph NE | 21% |
| Thursday Night | 57°F | Mostly Clear | 0 to 5 mph E | 7% |
| Friday | 81°F | Sunny | 0 to 5 mph SW | 2% |
| Friday Night | 62°F | Mostly Clear | 0 to 5 mph SW | 5% |
| Saturday | 83°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 5 to 10 mph SW | 15% |
| Saturday Night | 67°F | Slight Chance Showers And Thunderstorms | 5 mph SW | 30% |
| Sunday | 84°F | Chance Showers And Thunderstorms | 5 to 10 mph SW | 30% |
| Sunday Night | 66°F | Slight Chance Showers And Thunderstorms then Chance Showers And Thunderstorms | 5 to 10 mph SW | 50% |
| Monday | 82°F | Chance Rain Showers | 5 mph S | 44% |
| Monday Night | 65°F | Chance Showers And Thunderstorms | 5 mph W | 45% |
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 Aug 4, 2026.