Cimarron climate

Cimarron Frost Dates and Growing Season

NOAA 1991-2020 normals for Cimarron 4 Sw, 5.7 km from Cimarron, elevation 6540 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Cimarron 4 Sw. 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 May 11 and the first fall freeze around October 3, a growing season of about 143 days.

Median at 36°F
last May 24, first September 26
Median at 32°F
last May 11, first October 3
Median at 28°F
last May 1, first October 12

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°FJun 6Jun 2May 31May 27May 24May 21May 18May 14May 10
32°FMay 25May 20May 16May 13May 11May 8May 6May 3Apr 30
28°FMay 13May 9May 6May 3May 1Apr 28Apr 25Apr 22Apr 17
24°FMay 5Apr 30Apr 27Apr 24Apr 21Apr 18Apr 15Apr 11Apr 6
20°FApr 27Apr 22Apr 18Apr 14Apr 10Apr 6Apr 3Mar 30Mar 24
16°FApr 17Apr 9Apr 5Apr 1Mar 28Mar 24Mar 19Mar 14Mar 8

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 13Sep 17Sep 21Sep 23Sep 26Sep 28Oct 1Oct 2Oct 5
32°FSep 21Sep 26Sep 29Oct 1Oct 3Oct 5Oct 8Oct 11Oct 15
28°FSep 30Oct 4Oct 7Oct 9Oct 12Oct 14Oct 17Oct 19Oct 23
24°FOct 8Oct 12Oct 15Oct 18Oct 20Oct 23Oct 26Oct 29Nov 2
20°FOct 16Oct 21Oct 25Oct 28Oct 31Nov 2Nov 5Nov 8Nov 13
16°FOct 25Oct 30Nov 2Nov 4Nov 7Nov 10Nov 14Nov 17Nov 22

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°F141135131128124121117112106
32°F160155151147143140137132125
28°F180174170166163160156151144
24°F200193189185181177173168162
20°F223215210205201196192187180
16°F247239233227223218212205197

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
5,708
Cooling degree days, base 65°F
287
Growing degree days, base 40°F
4,583
Growing degree days, base 45°F
3,358
Growing degree days, base 50°F
2,317
Growing degree days, base 55°F
1,459
Growing degree days, base 60°F
777

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January99700
February84102
March713016
April498061
May2648228
June5167467
July10120575
August2277519
September13615331
October4270107
November741011
December1,00701

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 5.7 km from Cimarron. 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 USC00291813 (Cimarron 4 Sw). Public domain.