Dulce climate

Dulce Frost Dates and Growing Season

NOAA 1991-2020 normals for Dulce, 0.2 km from Dulce, elevation 6793 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Dulce. 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 June 9 and the first fall freeze around September 22, a growing season of about 103 days.

Median at 36°F
last June 24, first September 12
Median at 32°F
last June 9, first September 22
Median at 28°F
last May 23, first September 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°FJul 9Jul 4Jun 30Jun 27Jun 24Jun 21Jun 18Jun 14Jun 9
32°FJun 27Jun 21Jun 16Jun 13Jun 9Jun 6Jun 3May 30May 25
28°FJun 10Jun 4May 31May 27May 23May 19May 16May 11May 6
24°FMay 21May 15May 10May 7May 4May 1Apr 29Apr 25Apr 21
20°FMay 5May 1Apr 28Apr 24Apr 20Apr 16Apr 12Apr 8Apr 2
16°FApr 22Apr 15Apr 10Apr 5Apr 2Mar 30Mar 24Mar 18Mar 12

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 28Sep 2Sep 6Sep 10Sep 12Sep 14Sep 17Sep 20Sep 24
32°FSep 10Sep 14Sep 17Sep 20Sep 22Sep 24Sep 26Sep 28Oct 1
28°FSep 20Sep 23Sep 26Sep 28Sep 30Oct 2Oct 4Oct 7Oct 12
24°FSep 29Oct 1Oct 4Oct 7Oct 9Oct 12Oct 16Oct 18Oct 23
20°FOct 5Oct 10Oct 15Oct 18Oct 20Oct 24Oct 27Nov 1Nov 4
16°FOct 15Oct 20Oct 25Oct 29Nov 1Nov 4Nov 7Nov 11Nov 16

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°F989286817874706454
32°F12311711210710399959083
28°F152144138134130126122117109
24°F176169165161157154150144137
20°F206199193188183179174168160
16°F236229223217212207201194187

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
6,647
Cooling degree days, base 65°F
262
Growing degree days, base 40°F
4,014
Growing degree days, base 45°F
2,923
Growing degree days, base 50°F
2,010
Growing degree days, base 55°F
1,266
Growing degree days, base 60°F
681

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,18100
February93000
March79201
April576021
May3501145
June10730374
July10131586
August1989535
September16911297
October518051
November84301
December1,15300

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 0.2 km from Dulce. 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 USC00292608 (Dulce). Public domain.