Yukon climate

Yukon Frost Dates and Growing Season

NOAA 1991-2020 normals for Oklahoma City Post AP, 10.8 km from Yukon, elevation 1297 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Oklahoma City Post 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 2 and the first fall freeze around November 4, a growing season of about 216 days.

Median at 36°F
last April 13, first October 27
Median at 32°F
last April 2, first November 4
Median at 28°F
last March 19, first November 13

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°FApr 29Apr 23Apr 19Apr 16Apr 13Apr 9Apr 7Apr 3Mar 30
32°FApr 18Apr 11Apr 8Apr 5Apr 2Mar 30Mar 27Mar 21Mar 14
28°FApr 5Mar 31Mar 28Mar 23Mar 19Mar 14Mar 11Mar 6Feb 28
24°FMar 27Mar 20Mar 15Mar 11Mar 8Mar 4Feb 28Feb 24Feb 19
20°FMar 15Mar 9Mar 5Mar 2Feb 27Feb 23Feb 19Feb 13Jan 31
16°FMar 7Mar 2Feb 25Feb 20Feb 14Feb 8Feb 1Jan 27Jan 16

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 14Oct 18Oct 21Oct 24Oct 27Oct 30Nov 1Nov 4Nov 9
32°FOct 21Oct 27Oct 30Nov 1Nov 4Nov 6Nov 10Nov 13Nov 18
28°FOct 31Nov 3Nov 7Nov 10Nov 13Nov 16Nov 19Nov 23Nov 30
24°FNov 5Nov 11Nov 15Nov 20Nov 24Nov 27Dec 1Dec 4Dec 10
20°FNov 14Nov 22Nov 26Nov 30Dec 3Dec 8Dec 13Dec 19Dec 27
16°FNov 25Dec 2Dec 7Dec 13Dec 20Dec 25Jan 1Jan 7Jan 17

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°F216210205201196193189183178
32°F239232226221216212207202194
28°F262254247242237233229223213
24°F285275270264259253248241230
20°F309300293286282276270262252
16°F342328321314307301295287276

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
99% 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
3,432
Cooling degree days, base 65°F
2,167
Growing degree days, base 40°F
8,238
Growing degree days, base 45°F
6,727
Growing degree days, base 50°F
5,363
Growing degree days, base 55°F
4,153
Growing degree days, base 60°F
3,087

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January801020
February613246
March41414164
April19151330
May40188613
June1407856
July05861,051
August05411,006
September15293728
October16179397
November4467126
December749028

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 10.8 km from Yukon. 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 USW00003954 (Oklahoma City Post AP). Public domain.