Perry County climate

Perry County Frost Dates and Growing Season

NOAA 1991-2020 normals for Linden Wtp, 4.6 km from Perry County, elevation 505 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Linden Wtp. 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 12 and the first fall freeze around October 25, a growing season of about 197 days.

Median at 36°F
last April 23, first October 17
Median at 32°F
last April 12, first October 25
Median at 28°F
last April 1, first November 3

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 7May 2Apr 30Apr 26Apr 23Apr 20Apr 17Apr 13Apr 8
32°FApr 25Apr 22Apr 18Apr 15Apr 12Apr 8Apr 4Mar 31Mar 26
28°FApr 17Apr 11Apr 6Apr 3Apr 1Mar 29Mar 25Mar 20Mar 13
24°FApr 6Apr 2Mar 28Mar 23Mar 18Mar 14Mar 8Mar 2Feb 25
20°FMar 26Mar 17Mar 12Mar 6Mar 2Feb 27Feb 23Feb 16Feb 6
16°FMar 13Mar 5Feb 28Feb 24Feb 17Feb 12Feb 6Jan 31Jan 22

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 3Oct 8Oct 11Oct 14Oct 17Oct 19Oct 21Oct 24Oct 28
32°FOct 14Oct 18Oct 21Oct 23Oct 25Oct 28Oct 30Nov 2Nov 6
28°FOct 22Oct 27Oct 30Nov 1Nov 3Nov 5Nov 9Nov 13Nov 19
24°FNov 1Nov 4Nov 8Nov 11Nov 14Nov 18Nov 22Nov 27Dec 3
20°FNov 8Nov 14Nov 18Nov 23Nov 27Dec 1Dec 5Dec 12Dec 22
16°FNov 19Nov 28Dec 2Dec 8Dec 15Dec 23Dec 30Jan 5Jan 14

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°F196189184180177173169164158
32°F219211205201197194189185179
28°F242234228224218213208203197
24°F271261255248242237231225218
20°F303291283275269263256250240
16°F335323313306300294287277267

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
3,824
Cooling degree days, base 65°F
1,426
Growing degree days, base 40°F
7,168
Growing degree days, base 45°F
5,713
Growing degree days, base 50°F
4,405
Growing degree days, base 55°F
3,253
Growing degree days, base 60°F
2,260

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January851023
February666029
March4915112
April23629272
May69113509
June5275720
July0398863
August1371835
September28194617
October22036302
November504391
December753232

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 4.6 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 USC00405278 (Linden Wtp). Public domain.