Perry County climate

Perry County Frost Dates and Growing Season

NOAA 1991-2020 normals for New Lexington 2 Nw, 1.8 km from Perry County, elevation 877 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for New Lexington 2 Nw. 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 30 and the first fall freeze around October 17, a growing season of about 168 days.

Median at 36°F
last May 10, first October 5
Median at 32°F
last April 30, first October 17
Median at 28°F
last April 19, first October 28

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

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 23Sep 28Oct 1Oct 3Oct 5Oct 8Oct 11Oct 14Oct 18
32°FOct 4Oct 7Oct 11Oct 14Oct 17Oct 20Oct 22Oct 25Oct 29
28°FOct 15Oct 20Oct 23Oct 25Oct 28Oct 31Nov 1Nov 4Nov 8
24°FOct 26Oct 30Nov 1Nov 4Nov 6Nov 9Nov 11Nov 14Nov 19
20°FNov 4Nov 7Nov 11Nov 14Nov 17Nov 20Nov 24Nov 29Dec 3
16°FNov 12Nov 18Nov 22Nov 26Nov 30Dec 3Dec 8Dec 14Dec 22

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°F167161157154150146143138131
32°F186180177173168165161156149
28°F208203198194191187183178170
24°F234227222218214211208203196
20°F262254247242238233229224217
16°F289279272266261256251245235

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
5,864
Cooling degree days, base 65°F
679
Growing degree days, base 40°F
5,208
Growing degree days, base 45°F
4,018
Growing degree days, base 50°F
2,967
Growing degree days, base 55°F
2,059
Growing degree days, base 60°F
1,291

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,16504
February97904
March813029
April4505119
May19742323
June36137551
July4224685
August9189645
September9874429
October3968149
November713026
December1,00405

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 1.8 km from Perry County. 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 USC00335857 (New Lexington 2 Nw). Public domain.