Earlsboro climate

Earlsboro Frost Dates and Growing Season

NOAA 1991-2020 normals for Seminole, 14.2 km from Earlsboro, elevation 924 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Seminole. 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 5 and the first fall freeze around November 1, a growing season of about 210 days.

Median at 36°F
last April 16, first October 24
Median at 32°F
last April 5, first November 1
Median at 28°F
last March 24, first November 9

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 30Apr 26Apr 22Apr 19Apr 16Apr 13Apr 10Apr 6Mar 31
32°FApr 22Apr 17Apr 12Apr 8Apr 5Apr 2Mar 29Mar 25Mar 18
28°FApr 10Apr 4Mar 31Mar 28Mar 24Mar 20Mar 16Mar 11Mar 4
24°FMar 30Mar 24Mar 18Mar 14Mar 11Mar 7Mar 3Feb 28Feb 21
20°FMar 17Mar 11Mar 6Mar 3Feb 28Feb 24Feb 20Feb 14Feb 4
16°FMar 9Mar 3Feb 28Feb 22Feb 14Feb 8Feb 2Jan 27Jan 17

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 9Oct 15Oct 18Oct 21Oct 24Oct 27Oct 29Nov 1Nov 7
32°FOct 18Oct 23Oct 27Oct 30Nov 1Nov 4Nov 6Nov 10Nov 15
28°FOct 25Oct 31Nov 3Nov 6Nov 9Nov 12Nov 16Nov 21Nov 27
24°FNov 1Nov 6Nov 11Nov 16Nov 20Nov 25Nov 29Dec 2Dec 8
20°FNov 9Nov 18Nov 25Nov 29Dec 1Dec 5Dec 10Dec 18Dec 26
16°FNov 25Dec 2Dec 7Dec 13Dec 19Dec 24Dec 30Jan 5Jan 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°F211204199195191187183177171
32°F234226220215210206201196189
28°F259249243237232227222216208
24°F283273266259254249243235228
20°F310300292286279274268261251
16°F339330321313307301293282271

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
3,396
Cooling degree days, base 65°F
2,042
Growing degree days, base 40°F
8,119
Growing degree days, base 45°F
6,606
Growing degree days, base 50°F
5,242
Growing degree days, base 55°F
4,024
Growing degree days, base 60°F
2,958

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January806019
February609144
March42710150
April18844324
May38171599
June1382831
July05521,017
August0527992
September14281717
October14668398
November4395123
December729129

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 14.2 km from Earlsboro. 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 USC00348042 (Seminole). Public domain.