Kasigluk climate

Kasigluk Frost Dates and Growing Season

NOAA 1991-2020 normals for Bethel AP, 39.3 km from Kasigluk, elevation 102 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Bethel 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 21 and the first fall freeze around September 22, a growing season of about 122 days.

Median at 36°F
last June 2, first September 8
Median at 32°F
last May 21, first September 22
Median at 28°F
last May 11, first October 1

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 14Jun 10Jun 7Jun 4Jun 2Jun 1May 29May 25May 20
32°FJun 2May 31May 28May 24May 21May 19May 15May 12May 8
28°FMay 26May 21May 17May 13May 11May 8May 5May 3Apr 30
24°FMay 18May 13May 9May 5May 3May 2Apr 30Apr 25Apr 21
20°FMay 10May 5May 3Apr 30Apr 27Apr 24Apr 21Apr 18Apr 12
16°FMay 4Apr 30Apr 26Apr 24Apr 21Apr 18Apr 15Apr 11Apr 6

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 23Aug 29Sep 2Sep 5Sep 8Sep 11Sep 15Sep 17Sep 22
32°FSep 7Sep 12Sep 16Sep 19Sep 22Sep 25Sep 27Sep 30Oct 4
28°FSep 19Sep 24Sep 27Sep 29Oct 1Oct 4Oct 7Oct 10Oct 15
24°FSep 29Oct 3Oct 5Oct 7Oct 10Oct 13Oct 16Oct 19Oct 23
20°FOct 6Oct 10Oct 13Oct 16Oct 18Oct 21Oct 24Oct 27Oct 31
16°FOct 12Oct 16Oct 20Oct 22Oct 25Oct 28Oct 31Nov 3Nov 8

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°F1161091041019793888374
32°F140135130126122118114110104
28°F161156151146143140136132124
24°F180173168165161156152148141
20°F193186182178174171167162154
16°F207200196191188184180175168

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
12,228
Cooling degree days, base 65°F
6
Growing degree days, base 40°F
1,724
Growing degree days, base 45°F
1,039
Growing degree days, base 50°F
501
Growing degree days, base 55°F
175
Growing degree days, base 60°F
41

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,79900
February1,44800
March1,56500
April1,07900
May681015
June3532130
July2733200
August3451132
September569023
October1,01800
November1,39300
December1,70500

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 39.3 km from Kasigluk. 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 USW00026615 (Bethel AP). Public domain.