Allen climate

Allen Frost Dates and Growing Season

NOAA 1991-2020 normals for Holdenville 2SSE, 19.9 km from Allen, elevation 855 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Holdenville 2SSE. 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 6 and the first fall freeze around October 31, a growing season of about 206 days.

Median at 36°F
last April 17, first October 21
Median at 32°F
last April 6, first October 31
Median at 28°F
last March 23, first November 8

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 1Apr 27Apr 24Apr 20Apr 17Apr 13Apr 10Apr 6Apr 1
32°FApr 24Apr 18Apr 13Apr 9Apr 6Apr 3Mar 31Mar 26Mar 19
28°FApr 13Apr 5Apr 1Mar 29Mar 23Mar 20Mar 15Mar 11Mar 5
24°FMar 29Mar 22Mar 17Mar 12Mar 9Mar 6Mar 2Feb 28Feb 21
20°FMar 17Mar 11Mar 6Mar 3Feb 28Feb 23Feb 19Feb 13Feb 4
16°FMar 8Mar 2Feb 26Feb 19Feb 14Feb 9Feb 3Jan 29Jan 20

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 6Oct 12Oct 16Oct 19Oct 21Oct 24Oct 27Oct 31Nov 4
32°FOct 17Oct 22Oct 25Oct 28Oct 31Nov 2Nov 5Nov 9Nov 16
28°FOct 24Oct 30Nov 2Nov 5Nov 8Nov 12Nov 16Nov 21Nov 27
24°FNov 1Nov 6Nov 11Nov 15Nov 21Nov 25Nov 29Dec 2Dec 9
20°FNov 10Nov 18Nov 24Nov 28Dec 1Dec 5Dec 10Dec 16Dec 23
16°FNov 24Dec 1Dec 7Dec 12Dec 18Dec 23Dec 29Jan 4Jan 13

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°F207199194190187183178174168
32°F229221215210206202197192185
28°F254247241236231226220213203
24°F279270265259254249245239228
20°F305296289283278273268261252
16°F337325317309303297292285273

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
3,436
Cooling degree days, base 65°F
2,045
Growing degree days, base 40°F
8,102
Growing degree days, base 45°F
6,601
Growing degree days, base 50°F
5,244
Growing degree days, base 55°F
4,030
Growing degree days, base 60°F
2,963

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January814021
February615144
March4208156
April18146331
May37176605
June1394843
July05491,014
August0516981
September15284718
October15865386
November4566118
December738030

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 19.9 km from Allen. 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 USC00344235 (Holdenville 2SSE). Public domain.