Cimarron climate

Cimarron Frost Dates and Growing Season

NOAA 1991-2020 normals for Cimarron, 0.7 km from Cimarron, elevation 2703 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Cimarron. 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 20 and the first fall freeze around October 20, a growing season of about 182 days.

Median at 36°F
last April 30, first October 12
Median at 32°F
last April 20, first October 20
Median at 28°F
last April 10, first October 29

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 12May 8May 5May 2Apr 30Apr 28Apr 25Apr 21Apr 16
32°FMay 3Apr 30Apr 26Apr 23Apr 20Apr 17Apr 14Apr 10Apr 6
28°FApr 26Apr 21Apr 17Apr 13Apr 10Apr 6Apr 4Mar 31Mar 25
24°FApr 17Apr 10Apr 6Apr 3Mar 31Mar 27Mar 23Mar 18Mar 11
20°FApr 6Apr 1Mar 28Mar 24Mar 19Mar 14Mar 10Mar 7Mar 3
16°FMar 30Mar 22Mar 16Mar 12Mar 8Mar 6Mar 2Feb 28Feb 21

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 28Oct 2Oct 5Oct 9Oct 12Oct 14Oct 17Oct 20Oct 23
32°FOct 7Oct 12Oct 15Oct 18Oct 20Oct 23Oct 25Oct 28Nov 1
28°FOct 16Oct 20Oct 23Oct 26Oct 29Oct 31Nov 3Nov 5Nov 10
24°FOct 21Oct 26Oct 30Nov 2Nov 5Nov 8Nov 11Nov 14Nov 20
20°FOct 28Nov 2Nov 6Nov 10Nov 13Nov 17Nov 21Nov 25Nov 30
16°FNov 4Nov 10Nov 15Nov 19Nov 23Nov 27Dec 1Dec 5Dec 11

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°F180175171168164160156151145
32°F201194189186182178174169162
28°F222214209204200196192187181
24°F243234228223218213209204197
20°F263255249243238233228222213
16°F282275268262256251247240232

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
5,031
Cooling degree days, base 65°F
1,485
Growing degree days, base 40°F
6,543
Growing degree days, base 45°F
5,253
Growing degree days, base 50°F
4,107
Growing degree days, base 55°F
3,102
Growing degree days, base 60°F
2,229

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,04001
February84509
March640265
April35914182
May124101448
June11302741
July1460924
August2387849
September51190592
October30029248
November661145
December99603

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 0.7 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 USC00141522 (Cimarron). Public domain.