Frost Dates for Port Alsworth, AK
Elevation: 79 m
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.
May 12
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.
September 24
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 18
First Fall Frost
September 18
Hard Freeze (28°F)
Last Spring Hard Freeze
April 29
First Fall Hard Freeze
October 4
Growing Season
135 Days
May 12 to September 24
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 3b
Avg. annual minimum: −35 to −30°F
Köppen Climate
The Köppen climate classification system categorizes climates based on temperature and precipitation patterns.
Dsc
Subarctic (Dry Summer)
Cool, dry summers and cold winters. A rare climate found at high elevations. Very short growing season for cold-tolerant crops only.
Temperature
0°
20°
40°
60°
Avg High
Avg Temp
Avg Low
Light Frost (32°F)
Hard Frost (28°F)
Temperature table
| Month | Avg High | Avg Temp | Avg Low |
|---|---|---|---|
| January | 24° | 17° | 10° |
| February | 30° | 23° | 15° |
| March | 35° | 25° | 15° |
| April | 47° | 39° | 30° |
| May | 59° | 49° | 39° |
| June | 67° | 57° | 47° |
| July | 69° | 60° | 52° |
| August | 66° | 58° | 49° |
| September | 57° | 50° | 42° |
| October | 44° | 38° | 32° |
| November | 32° | 27° | 21° |
| December | 27° | 21° | 15° |
Precipitation
0"
2"
4"
4.1"
Precipitation table
| Month | Precipitation |
|---|---|
| January | 1.7 |
| February | 1.8 |
| March | 2.1 |
| April | 1.8 |
| May | 1.6 |
| June | 2.0 |
| July | 2.7 |
| August | 3.3 |
| September | 4.1 |
| October | 3.1 |
| November | 2.2 |
| December | 2.0 |
Sunrise / Sunset
Daylight
Longest: 18h 34m · Shortest: 5h 26m
Sunrise and sunset table
| Month | Sunrise | Sunset | Daylight |
|---|---|---|---|
| January | 8:51 AM | 3:09 PM | 6h 17m |
| February | 7:37 AM | 4:23 PM | 8h 45m |
| March | 6:20 AM | 5:40 PM | 11h 21m |
| April | 4:53 AM | 7:07 PM | 14h 15m |
| May | 3:34 AM | 8:26 PM | 16h 52m |
| June | 2:45 AM | 9:15 PM | 18h 31m |
| July | 3:06 AM | 8:54 PM | 17h 48m |
| August | 4:19 AM | 7:41 PM | 15h 23m |
| September | 5:44 AM | 6:16 PM | 12h 31m |
| October | 7:09 AM | 4:51 PM | 9h 43m |
| November | 8:29 AM | 3:31 PM | 7h 01m |
| December | 9:16 AM | 2:44 PM | 5h 29m |
Nearby Stations
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