Wheeler County climate

Wheeler County Frost Dates and Growing Season

NOAA 1991-2020 normals for Mitchell 2 E, 18.9 km from Wheeler County, elevation 3320 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Mitchell 2 E. 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 22 and the first fall freeze around October 4, a growing season of about 135 days.

Median at 36°F
last June 14, first September 19
Median at 32°F
last May 22, first October 4
Median at 28°F
last April 30, first October 22

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 30Jun 24Jun 20Jun 17Jun 14Jun 11Jun 7Jun 2May 27
32°FJun 11Jun 4May 31May 27May 22May 17May 13May 8May 1
28°FMay 18May 11May 6May 3Apr 30Apr 27Apr 23Apr 17Apr 11
24°FMay 1Apr 25Apr 19Apr 14Apr 8Apr 4Mar 29Mar 24Mar 15
20°FApr 12Apr 2Mar 28Mar 23Mar 17Mar 11Mar 4Feb 27Feb 19
16°FMar 20Mar 9Mar 1Feb 26Feb 21Feb 16Feb 11Feb 4Jan 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 1Sep 6Sep 11Sep 15Sep 19Sep 23Sep 26Oct 1Oct 5
32°FSep 16Sep 24Sep 29Oct 1Oct 4Oct 7Oct 11Oct 15Oct 20
28°FOct 4Oct 10Oct 15Oct 18Oct 22Oct 25Oct 28Oct 31Nov 7
24°FOct 18Oct 23Oct 29Nov 1Nov 3Nov 8Nov 12Nov 18Nov 25
20°FOct 26Nov 2Nov 8Nov 12Nov 17Nov 21Nov 26Dec 1Dec 8
16°FNov 4Nov 12Nov 18Nov 24Nov 29Dec 2Dec 8Dec 16Dec 27

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°F1201121071029691868071
32°F161152146140135130123116108
28°F201190182177173168163157147
24°F242230222215209203198191179
20°F283270261252245238231223210
16°F321308298290282274266259246

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
6,276
Cooling degree days, base 65°F
302
Growing degree days, base 40°F
3,969
Growing degree days, base 45°F
2,816
Growing degree days, base 50°F
1,899
Growing degree days, base 55°F
1,189
Growing degree days, base 60°F
658

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January95302
February80801
March752010
April599035
May4027134
June22823257
July56124533
August57110518
September19536304
October484390
November755015
December98701

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 18.9 km from Wheeler County. 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 USC00355638 (Mitchell 2 E). Public domain.