Frost Dates for Petersburg, AK

Based on data from Petersburg 1 weather station, 1 miles away

Elevation: 36 ft

Frost Dates

Last Spring Frost (50%) A 50% chance that the last spring frost has already passed by this date. Most gardeners use this as their primary planting guide. April 29
First Fall Frost (50%) A 50% chance that the first fall frost has occurred by this date. Plan to harvest or protect tender plants before this date. October 17

30% Probability

Only a 30% chance of frost remaining by this date. Use these dates for a safer planting window, especially for tender plants sensitive to cold.
Last Spring Frost May 4
First Fall Frost October 9

Hard Freeze (28°F)

Last Spring Hard Freeze April 11
First Fall Hard Freeze November 1
56.81°N, 132.96°W © OpenStreetMap

Growing Season

171 Days April 29 to October 17

USDA Hardiness Zone

Hardiness zones indicate which perennial plants can survive winter in your area. For annual vegetables, frost dates and growing season length matter more than hardiness zone.
Zone 7a

Avg. annual minimum: 0 to 5°F

Learn more

Köppen Climate

The Köppen climate classification system categorizes climates based on temperature and precipitation patterns.
Dfb Warm-Summer Continental

Warm summers and cold, snowy winters. A shorter growing season than hot-summer continental. Hardy vegetables, root crops, and cool-season greens do well. Season extension is valuable.

Köppen climate map

Temperature

Avg High Avg Temp Avg Low Light Frost (32°F) Hard Frost (28°F)
Temperature table
Average monthly temperatures (°F)
Month Avg High Avg Temp Avg Low
January35°31°27°
February37°32°28°
March40°35°30°
April48°42°35°
May55°49°42°
June60°54°48°
July62°56°51°
August61°56°50°
September56°51°46°
October47°43°39°
November39°36°32°
December35°32°28°

Precipitation

Precipitation table
Average monthly precipitation (inches)
MonthPrecipitation
January10.3
February8.0
March7.9
April6.9
May7.0
June6.4
July7.4
August9.4
September12.5
October13.7
November11.3
December11.4

Sunrise / Sunset

Daylight Alaska Time (AKT) Longest: 17h 32m · Shortest: 6h 28m
Sunrise and sunset table
Sunrise, sunset, and daylight on the 15th of each month (Alaska Time (AKT))
Month Sunrise Sunset Daylight
January8:27 AM3:35 PM7h 08m
February7:31 AM4:42 PM9h 11m
March7:19 AM6:44 PM11h 25m
April5:53 AM7:51 PM13h 57m
May4:43 AM8:53 PM16h 11m
June4:07 AM9:37 PM17h 30m
July4:29 AM9:26 PM16h 56m
August5:28 AM8:24 PM14h 56m
September6:33 AM6:60 PM12h 27m
October7:37 AM5:37 PM10h 00m
November7:45 AM3:29 PM7h 44m
December8:33 AM3:03 PM6h 30m

Nearby Stations

Wrangell AP, AK April 11 - November 1 Pt Baker, AKApril 19 - October 25 Thorne Bay, AKMay 1 - October 13 Klawock AP, AK April 29 - October 16 Craig, AKApril 14 - November 1 Ketchikan 10n, AK April 20 - October 26

Plan Your Garden with Planter

Now that you know your frost dates, use Planter to plan your veggie garden! Planter is an easy drag-and-drop garden planner with personalized planting schedules.

Try Planter For Free

Available everywhere: iOS, Android, web, and more!

Planter app garden planner preview