Southwest Harbor, ME Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Southwest Harbor, a community in Hancock County, Maine.
This Afternoon
77°F
Sunny
Sunny, with a high near 77. Northwest wind around 12 mph, with gusts as high as 22 mph.
7-day forecast for Southwest Harbor
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 77°F | Sunny | 12 mph NW | 0% |
| Tonight | 48°F | Clear | 8 to 12 mph NW | 0% |
| Saturday | 63°F | Sunny | 8 mph NW | 0% |
| Saturday Night | 49°F | Partly Cloudy | 1 to 5 mph S | 0% |
| Sunday | 62°F | Mostly Cloudy then Slight Chance Light Rain | 2 to 9 mph S | 18% |
| Sunday Night | 50°F | Chance Light Rain | 2 to 6 mph SW | 42% |
| Monday | 65°F | Mostly Sunny | 7 mph N | 10% |
| Monday Night | 47°F | Partly Cloudy | 5 to 8 mph N | 0% |
| Tuesday | 63°F | Mostly Sunny | 5 to 8 mph NE | 1% |
| Tuesday Night | 47°F | Partly Cloudy | 0 to 6 mph NE | 1% |
| Wednesday | 63°F | Sunny | 6 to 10 mph NE | 0% |
| Wednesday Night | 47°F | Partly Cloudy | 1 to 5 mph NE | 4% |
| Thursday | 62°F | Mostly Sunny then Slight Chance Rain Showers | 3 to 8 mph NE | 18% |
| Thursday Night | 48°F | Chance Rain Showers | 3 to 7 mph NE | 28% |
Forecast source: National Weather Service (api.weather.gov) for Southwest Harbor (44.278, -68.329). Updated through the day.
Growing snapshot for Southwest Harbor
Last spring frost
Apr 27
First fall frost
Oct 22
Growing season
177 days
Hardiness zone
6a
More local growing data for Southwest Harbor: nearby ZIP 04679 weather · frost dates · planting calendar · Maine frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Acadia Np, Me (7.1 mi from Southwest Harbor). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 18, 2026.