King Cove climate

King Cove Frost Dates and Growing Season

NOAA 1991-2020 normals for Cold Bay AP, 31.8 km from King Cove, elevation 78 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Cold Bay AP. A median date has an even chance of a later freeze in spring, or an earlier one in fall.

The last spring freeze typically comes around May 25 and the first fall freeze around October 4, a growing season of about 131 days.

Median at 36°F
last June 7, first September 20
Median at 32°F
last May 25, first October 4
Median at 28°F
last May 8, first October 21

Last freeze in spring

The chance of a later freeze than the date shown. At 10 percent, one spring in ten still freezes after the date; planting after the 10 percent date for 32°F is the cautious choice.

Threshold10%20%30%40%50%60%70%80%90%
36°FJun 25Jun 19Jun 14Jun 10Jun 7Jun 4Jun 1May 29May 23
32°FJun 10Jun 5Jun 1May 29May 25May 22May 18May 15May 9
28°FMay 27May 20May 15May 11May 8May 5May 3Apr 29Apr 23
24°FMay 11May 6May 2Apr 27Apr 24Apr 21Apr 16Apr 11Apr 6
20°FApr 26Apr 19Apr 14Apr 10Apr 7Apr 4Apr 1Mar 29Mar 22
16°FApr 12Apr 6Apr 2Mar 31Mar 28Mar 23Mar 17Mar 9Feb 24

First freeze in fall

The chance of an earlier freeze than the date shown. At 10 percent, one fall in ten freezes before the date.

Threshold10%20%30%40%50%60%70%80%90%
36°FAug 23Sep 6Sep 12Sep 16Sep 20Sep 23Sep 26Sep 30Oct 4
32°FSep 20Sep 26Sep 30Oct 2Oct 4Oct 7Oct 11Oct 14Oct 20
28°FOct 4Oct 8Oct 13Oct 17Oct 21Oct 25Oct 28Nov 1Nov 6
24°FOct 21Oct 27Oct 31Nov 3Nov 7Nov 11Nov 15Nov 20Nov 27
20°FNov 2Nov 9Nov 14Nov 19Nov 23Nov 26Dec 1Dec 5Dec 12
16°FNov 14Nov 22Nov 27Dec 2Dec 6Dec 11Dec 17Dec 25Jan 2

Growing season length

Days between the last spring and first fall freeze at each threshold, with the chance of a season at least that long.

Threshold10%20%30%40%50%60%70%80%90%
36°F12211511010510095898370
32°F154146141136131127122117109
28°F189180175170165160154148140
24°F223215209203199193188183174
20°F255246240234229224219212203
16°F289279271263256251246238228

How often it gets that cold

The share of years with at least one night at or below each temperature.

36°F or colder
100% of years
32°F or colder
100% of years
28°F or colder
100% of years
24°F or colder
100% of years
20°F or colder
100% of years
16°F or colder
100% of years

Degree days

A degree day is one degree of the daily mean temperature beyond a base, for one day. Heating degree days count cold (the fuel a house burns), cooling degree days heat, growing degree days the warmth a crop needs; each crop has its own base.

Heating degree days, base 65°F
9,363
Cooling degree days, base 65°F
0
Growing degree days, base 40°F
1,406
Growing degree days, base 45°F
666
Growing degree days, base 50°F
195
Growing degree days, base 55°F
23
Growing degree days, base 60°F
1

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,13300
February97300
March1,08800
April90000
May74400
June539011
July417066
August383092
September498025
October73501
November89300
December1,06200

What this means

NOAA computes these from the daily lows at the station over 1991-2020, fitting the dates of each year's last and first freeze to a distribution, so a date can be stated at any level of risk. 36°F is a frost risk for tender plants on a clear, calm night, since the ground cools below the air above it; 32°F is a freeze; 28°F is a hard freeze that kills most annuals.

The station is 31.8 km from King Cove. Low ground, valleys and open fields freeze earlier and later than a town center or a hillside.

More

Sources

NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USW00025624 (Cold Bay AP). Public domain.