Petersburg, AK Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Petersburg, a community in Petersburg Borough County, Alaska.
Tonight
47°F
Mostly Cloudy
Mostly cloudy, with a low around 47. Northwest wind 10 to 15 mph.
7-day forecast for Petersburg
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 47°F | Mostly Cloudy | 10 to 15 mph NW | 0% |
| Tuesday | 62°F | Partly Sunny | 10 to 15 mph NW | 0% |
| Tuesday Night | 47°F | Mostly Cloudy | 5 to 15 mph NW | 3% |
| Wednesday | 64°F | Partly Sunny then Slight Chance Light Rain | 5 to 10 mph NW | 16% |
| Wednesday Night | 46°F | Partly Cloudy | 5 to 10 mph NW | 14% |
| Thursday | 63°F | Partly Sunny | 5 mph NW | 3% |
| Thursday Night | 48°F | Mostly Cloudy | 0 to 5 mph N | 8% |
| Friday | 62°F | Partly Sunny | 0 mph | 12% |
| Friday Night | 50°F | Slight Chance Rain Showers | 0 mph | 18% |
| Saturday | 63°F | Slight Chance Rain Showers | 0 mph | 22% |
| Saturday Night | 49°F | Slight Chance Rain Showers then Mostly Cloudy | 0 mph | 21% |
| Sunday | 64°F | Partly Sunny | 0 to 5 mph N | 0% |
| Sunday Night | 49°F | Mostly Cloudy | 0 to 5 mph NE | 0% |
| Monday | 65°F | Partly Sunny | 0 mph | 5% |
Forecast source: National Weather Service (api.weather.gov) for Petersburg (56.757, -132.875). Updated through the day.
Growing snapshot for Petersburg
Last spring frost
Apr 29
First fall frost
Oct 17
Growing season
169 days
More local growing data for Petersburg: nearby ZIP 99833 weather · frost dates · planting calendar · Alaska frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Petersburg 1, Ak (9.7 mi from Petersburg). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.