Wayne County climate

Wayne County Frost Dates and Growing Season

NOAA 1991-2020 normals for Richmond Wtr Wks, 11.3 km from Wayne County, elevation 1005 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Richmond Wtr Wks. 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 24 and the first fall freeze around October 20, a growing season of about 180 days.

Median at 36°F
last May 3, first October 10
Median at 32°F
last April 24, first October 20
Median at 28°F
last April 10, first October 30

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 19May 12May 9May 6May 3Apr 30Apr 27Apr 23Apr 19
32°FMay 10May 5Apr 30Apr 27Apr 24Apr 20Apr 17Apr 13Apr 8
28°FApr 28Apr 21Apr 18Apr 14Apr 10Apr 6Apr 3Mar 31Mar 26
24°FApr 15Apr 8Apr 4Apr 1Mar 30Mar 27Mar 23Mar 20Mar 15
20°FApr 3Mar 30Mar 26Mar 23Mar 20Mar 17Mar 13Mar 8Mar 3
16°FMar 25Mar 20Mar 16Mar 13Mar 9Mar 5Mar 2Feb 26Feb 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°FSep 26Oct 1Oct 5Oct 8Oct 10Oct 12Oct 15Oct 18Oct 22
32°FOct 7Oct 12Oct 15Oct 18Oct 20Oct 23Oct 25Oct 28Nov 1
28°FOct 17Oct 21Oct 24Oct 27Oct 30Nov 1Nov 3Nov 6Nov 12
24°FOct 29Nov 1Nov 4Nov 6Nov 9Nov 12Nov 15Nov 20Nov 26
20°FNov 7Nov 12Nov 16Nov 19Nov 23Nov 26Dec 1Dec 4Dec 12
16°FNov 15Nov 22Nov 28Dec 1Dec 4Dec 8Dec 14Dec 20Dec 26

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°F179173168164160156152146139
32°F200193189185180176171166159
28°F221215210206202197192187179
24°F246238232229225220216211203
20°F271263256252247243237231224
16°F296287281275270265259253244

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
5,535
Cooling degree days, base 65°F
941
Growing degree days, base 40°F
5,726
Growing degree days, base 45°F
4,494
Growing degree days, base 50°F
3,399
Growing degree days, base 55°F
2,439
Growing degree days, base 60°F
1,619

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,15003
February94507
March752143
April39210153
May15076397
June20202633
July2286749
August6244704
September80107479
October35015186
November684038
December1,00607

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 11.3 km from Wayne County. 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 USC00127370 (Richmond Wtr Wks). Public domain.