Kupreanof, AK Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Kupreanof, a city in Petersburg Borough County, Alaska.
Tonight
51°F
Heavy Rain
Rain before 1am, then rain showers. Cloudy, with a low around 51. Southeast wind 10 to 15 mph. Chance of precipitation is 100%. New rainfall amounts between 1 and 2 inches possible.
7-day forecast for Kupreanof
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 51°F | Heavy Rain | 10 to 15 mph SE | 100% |
| Sunday | 55°F | Showers And Thunderstorms | 10 mph SE | 100% |
| Sunday Night | 45°F | Showers And Thunderstorms | 5 to 10 mph SE | 100% |
| Monday | 53°F | Rain Showers | 5 mph SE | 100% |
| Monday Night | 42°F | Rain Showers | 5 to 10 mph SE | 100% |
| Tuesday | 52°F | Rain Showers | 10 mph SE | 100% |
| Tuesday Night | 40°F | Rain Showers | 5 to 10 mph SE | 100% |
| Wednesday | 51°F | Rain Showers | 5 to 10 mph SE | 100% |
| Wednesday Night | 41°F | Rain Showers | 5 mph E | 76% |
| Thursday | 53°F | Chance Rain Showers | 0 to 5 mph E | 39% |
| Thursday Night | 40°F | Chance Rain Showers | 0 mph | 26% |
| Friday | 55°F | Chance Rain Showers | 0 to 5 mph NE | 34% |
| Friday Night | 41°F | Chance Rain Showers | 0 to 5 mph E | 52% |
| Saturday | 53°F | Rain Showers Likely | 5 to 10 mph SE | 70% |
Forecast source: National Weather Service (api.weather.gov) for Kupreanof (56.821, -132.972). Updated through the day.
Growing snapshot for Kupreanof
Last spring frost
Apr 29
First fall frost
Oct 17
Growing season
169 days
More local growing data for Kupreanof: 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 Kupreanof). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.