Tierra Amarilla climate

Tierra Amarilla Frost Dates and Growing Season

NOAA 1991-2020 normals for Tierra Amarilla 4 N, 7.4 km from Tierra Amarilla, elevation 7464 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Tierra Amarilla 4 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 June 11 and the first fall freeze around September 20, a growing season of about 98 days.

Median at 32°F
last June 11, first September 20
Median at 28°F
last May 28, first September 28

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°F–––––––––
32°FJun 26Jun 21Jun 17Jun 14Jun 11Jun 8Jun 5Jun 2May 29
28°FJun 11Jun 6Jun 3May 31May 28May 23May 20May 16May 11
24°FMay 28May 22May 17May 14May 11May 7May 3May 1Apr 26
20°FMay 11May 5May 2Apr 30Apr 26Apr 23Apr 19Apr 15Apr 11
16°FApr 27Apr 22Apr 18Apr 14Apr 11Apr 8Apr 5Apr 2Mar 26

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°F–––––––––
32°FSep 8Sep 12Sep 15Sep 18Sep 20Sep 22Sep 24Sep 26Sep 29
28°FSep 16Sep 21Sep 24Sep 26Sep 28Sep 30Oct 3Oct 6Oct 10
24°FSep 26Sep 29Oct 2Oct 4Oct 7Oct 10Oct 13Oct 17Oct 21
20°FOct 3Oct 8Oct 13Oct 16Oct 19Oct 21Oct 25Oct 29Nov 2
16°FOct 13Oct 19Oct 22Oct 27Oct 30Nov 1Nov 4Nov 8Nov 13

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°F938883797673686456
32°F1161101051029895928680
28°F142135130126122119114109102
24°F168162157153149145141135129
20°F196188183178174170166162155
16°F222214208204199195190185178

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
7,928
Cooling degree days, base 65°F
58
Growing degree days, base 40°F
3,142
Growing degree days, base 45°F
2,185
Growing degree days, base 50°F
1,406
Growing degree days, base 55°F
787
Growing degree days, base 60°F
322

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,30400
February1,07700
March93900
April70504
May475063
June1874271
July4236459
August7317409
September2801187
October631015
November94200
December1,27400

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 7.4 km from Tierra Amarilla. 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 USC00298845 (Tierra Amarilla 4 N). Public domain.