Guymon climate

Guymon Frost Dates and Growing Season

NOAA 1991-2020 normals for Guymon Muni AP, 2.2 km from Guymon, elevation 3123 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Guymon Muni AP. 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 18 and the first fall freeze around October 23, a growing season of about 188 days.

Median at 36°F
last April 28, first October 14
Median at 32°F
last April 18, first October 23
Median at 28°F
last April 8, first November 1

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 10May 5May 2Apr 30Apr 28Apr 25Apr 22Apr 19Apr 14
32°FMay 1Apr 27Apr 23Apr 20Apr 18Apr 15Apr 12Apr 8Apr 4
28°FApr 23Apr 18Apr 14Apr 11Apr 8Apr 5Apr 2Mar 29Mar 23
24°FApr 14Apr 7Apr 4Apr 2Mar 29Mar 25Mar 21Mar 15Mar 8
20°FApr 3Mar 28Mar 22Mar 18Mar 13Mar 9Mar 6Mar 3Feb 26
16°FMar 21Mar 15Mar 9Mar 6Mar 3Feb 28Feb 24Feb 19Feb 12

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°FOct 2Oct 6Oct 9Oct 12Oct 14Oct 17Oct 19Oct 22Oct 26
32°FOct 11Oct 16Oct 19Oct 21Oct 23Oct 26Oct 28Oct 31Nov 3
28°FOct 19Oct 23Oct 27Oct 30Nov 1Nov 3Nov 5Nov 8Nov 12
24°FOct 27Oct 31Nov 2Nov 5Nov 8Nov 11Nov 13Nov 17Nov 22
20°FNov 1Nov 6Nov 11Nov 14Nov 17Nov 20Nov 24Nov 29Dec 4
16°FNov 9Nov 16Nov 21Nov 24Nov 27Dec 1Dec 4Dec 9Dec 15

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°F185179175172169166162157150
32°F205200196191188184180175168
28°F227220215210206203198194187
24°F247240235230225220216211204
20°F270262256252246242238232224
16°F299288279273267262257251243

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
4,293
Cooling degree days, base 65°F
1,640
Growing degree days, base 40°F
7,059
Growing degree days, base 45°F
5,667
Growing degree days, base 50°F
4,437
Growing degree days, base 55°F
3,365
Growing degree days, base 60°F
2,436

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January89006
February721121
March545486
April28919224
May90121498
June4338784
July0488953
August1418882
September35213630
October25237286
November582160
December88507

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 2.2 km from Guymon. 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 USW00003030 (Guymon Muni AP). Public domain.