Cordova climate

Cordova Frost Dates and Growing Season

NOAA 1991-2020 normals for Cordova N, 1.5 km from Cordova, elevation 25 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Cordova N. 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 April 24 and the first fall freeze around October 19, a growing season of about 176 days.

Median at 36°F
last May 12, first October 3
Median at 32°F
last April 24, first October 19
Median at 28°F
last April 7, first October 30

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°FMay 31May 23May 18May 15May 12May 10May 6May 3Apr 30
32°FMay 8May 4May 1Apr 27Apr 24Apr 20Apr 17Apr 14Apr 10
28°FApr 23Apr 17Apr 13Apr 10Apr 7Apr 5Apr 3Mar 31Mar 22
24°FApr 13Apr 7Apr 4Apr 2Mar 30Mar 25Mar 20Mar 15Mar 7
20°FApr 5Mar 31Mar 25Mar 19Mar 14Mar 9Mar 3Feb 22Feb 4
16°FMar 24Mar 14Mar 8Mar 2Feb 25Feb 15Feb 5Jan 27Jan 14

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°FSep 21Sep 26Sep 29Oct 1Oct 3Oct 5Oct 8Oct 13Oct 19
32°FOct 4Oct 8Oct 12Oct 16Oct 19Oct 22Oct 25Oct 29Nov 3
28°FOct 14Oct 19Oct 23Oct 27Oct 30Nov 2Nov 6Nov 12Nov 20
24°FOct 23Oct 30Nov 2Nov 7Nov 12Nov 18Nov 23Nov 29Dec 9
20°FNov 1Nov 7Nov 14Nov 21Nov 28Dec 4Dec 13Dec 26Jan 5
16°FNov 11Nov 27Dec 5Dec 22Jan 1Jan 8Jan 15Jan 28Feb 9

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°F163157152148144140135131122
32°F197190185181176172167163154
28°F231221215210205201197191183
24°F262251243236230222217210202
20°F303291278270260252242234223
16°F354333323311303296287277260

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
99% of years
16°F or colder
94% 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
8,170
Cooling degree days, base 65°F
0
Growing degree days, base 40°F
2,074
Growing degree days, base 45°F
1,193
Growing degree days, base 50°F
549
Growing degree days, base 55°F
149
Growing degree days, base 60°F
16

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,02600
February90200
March97700
April75901
May572016
June374093
July2620204
August2790187
September449047
October71303
November88500
December97300

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 1.5 km from Cordova. 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 USC00502173 (Cordova N). Public domain.