Port Angeles climate

Port Angeles Frost Dates and Growing Season

NOAA 1991-2020 normals for Port Angeles, 0.5 km from Port Angeles, elevation 90 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Port Angeles. 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 March 12 and the first fall freeze around November 19, a growing season of about 252 days.

Median at 36°F
last April 9, first November 1
Median at 32°F
last March 12, first November 19
Median at 28°F
last February 5, first December 8

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°FApr 28Apr 21Apr 16Apr 12Apr 9Apr 6Apr 3Mar 31Mar 24
32°FApr 1Mar 26Mar 21Mar 17Mar 12Mar 7Mar 2Feb 26Feb 17
28°FMar 6Feb 28Feb 22Feb 16Feb 5Jan 30Jan 17Jan 7Dec 24
24°FFeb 17Feb 2Jan 24Jan 16Jan 7Jan 1Dec 21Dec 13Dec 5
20°FJan 31Jan 22Jan 16Jan 8Jan 2Dec 23Dec 14Dec 9Dec 2
16°F–––––––––

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°FOct 17Oct 22Oct 25Oct 29Nov 1Nov 4Nov 8Nov 12Nov 18
32°FNov 1Nov 7Nov 12Nov 16Nov 19Nov 22Nov 26Dec 1Dec 8
28°FNov 17Nov 24Nov 29Dec 2Dec 8Dec 15Dec 22Jan 1Jan 15
24°FNov 28Dec 3Dec 7Dec 13Dec 20Dec 28Jan 5Jan 15Jan 30
20°FDec 1Dec 7Dec 11Dec 21Jan 1Jan 6Jan 15Jan 21Jan 31
16°F–––––––––

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°F227219213208204199195188180
32°F284272264257252246240233222
28°F352337327317310301292283269
24°F365365365362353345337328314
20°F365365365365365365365365349
16°F365365365365365365365365365

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
96% of years
24°F or colder
62% of years
20°F or colder
18% of years
16°F or colder
2% 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
5,494
Cooling degree days, base 65°F
26
Growing degree days, base 40°F
3,814
Growing degree days, base 45°F
2,402
Growing degree days, base 50°F
1,363
Growing degree days, base 55°F
613
Growing degree days, base 60°F
167

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January75601
February65700
March65703
April509026
May3521127
June2374218
July13811338
August1308343
September2143239
October456061
November62906
December75901

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 0.5 km from Port Angeles. Low ground, valleys and open fields freeze earlier and later than a town center or a hillside.

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Sources

NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USC00456624 (Port Angeles). Public domain.