La Junta climate

La Junta Frost Dates and Growing Season

NOAA 1991-2020 normals for La Junta, 0.3 km from La Junta, elevation 4089 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for La Junta. 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 26 and the first fall freeze around October 15, a growing season of about 171 days.

Median at 36°F
last May 6, first October 7
Median at 32°F
last April 26, first October 15
Median at 28°F
last April 15, first October 24

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 19May 15May 11May 9May 6May 4May 1Apr 29Apr 23
32°FMay 9May 5May 2Apr 30Apr 26Apr 23Apr 20Apr 16Apr 10
28°FApr 29Apr 24Apr 21Apr 18Apr 15Apr 11Apr 8Apr 4Mar 31
24°FApr 20Apr 14Apr 9Apr 6Apr 3Mar 31Mar 27Mar 22Mar 16
20°FApr 8Apr 3Mar 31Mar 26Mar 20Mar 16Mar 12Mar 8Mar 3
16°FApr 1Mar 22Mar 16Mar 11Mar 7Mar 4Mar 1Feb 26Feb 19

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 26Sep 30Oct 3Oct 5Oct 7Oct 9Oct 12Oct 15Oct 18
32°FOct 3Oct 7Oct 10Oct 12Oct 15Oct 18Oct 20Oct 23Oct 26
28°FOct 11Oct 16Oct 19Oct 22Oct 24Oct 26Oct 29Nov 1Nov 5
24°FOct 20Oct 24Oct 28Oct 31Nov 2Nov 5Nov 7Nov 10Nov 14
20°FOct 28Nov 1Nov 5Nov 8Nov 11Nov 13Nov 16Nov 20Nov 24
16°FNov 2Nov 7Nov 12Nov 16Nov 20Nov 23Nov 27Dec 1Dec 7

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°F169163159156153150145141135
32°F188182178174171168163159154
28°F210204200195191188183178172
24°F235227221216213208204198192
20°F258249243238234229224217209
16°F280271265259253248242236227

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
5,266
Cooling degree days, base 65°F
1,180
Growing degree days, base 40°F
6,023
Growing degree days, base 45°F
4,762
Growing degree days, base 50°F
3,656
Growing degree days, base 55°F
2,692
Growing degree days, base 60°F
1,871

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,04001
February83706
March641050
April3965144
May16062382
June13246682
July1392855
August2329792
September61136529
October35811189
November720023
December1,03702

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 0.3 km from La Junta. 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 USC00054724 (La Junta). Public domain.