Wayne County climate

Wayne County Frost Dates and Growing Season

NOAA 1991-2020 normals for Dunlow 1 Sw, 21.9 km from Wayne County, elevation 1113 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Dunlow 1 Sw. 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 13 and the first fall freeze around October 26, a growing season of about 197 days.

Median at 36°F
last April 27, first October 18
Median at 32°F
last April 13, first October 26
Median at 28°F
last March 31, first November 6

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 16May 10May 5May 1Apr 27Apr 23Apr 18Apr 15Apr 9
32°FMay 4Apr 27Apr 20Apr 16Apr 13Apr 9Apr 5Apr 1Mar 27
28°FApr 17Apr 10Apr 5Apr 2Mar 31Mar 28Mar 24Mar 20Mar 14
24°FApr 6Apr 1Mar 28Mar 25Mar 22Mar 18Mar 14Mar 9Mar 1
20°FMar 29Mar 23Mar 18Mar 15Mar 10Mar 5Mar 1Feb 25Feb 14
16°FMar 18Mar 12Mar 7Mar 3Feb 28Feb 21Feb 15Feb 7Feb 1

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 7Oct 10Oct 13Oct 15Oct 18Oct 20Oct 22Oct 25Oct 28
32°FOct 14Oct 18Oct 21Oct 24Oct 26Oct 29Oct 31Nov 3Nov 7
28°FOct 24Oct 30Nov 1Nov 4Nov 6Nov 9Nov 13Nov 16Nov 23
24°FNov 3Nov 7Nov 11Nov 15Nov 18Nov 22Nov 27Dec 2Dec 8
20°FNov 11Nov 17Nov 23Nov 27Dec 1Dec 5Dec 11Dec 18Dec 27
16°FNov 24Dec 1Dec 6Dec 12Dec 19Dec 25Dec 31Jan 6Jan 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°F193187182178173169164159151
32°F217210205201197193187180172
28°F244234229224220215212205197
24°F271261255249244239235228221
20°F298287281274269262256249240
16°F324314306300294288280274261

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
4,569
Cooling degree days, base 65°F
1,007
Growing degree days, base 40°F
6,300
Growing degree days, base 45°F
4,941
Growing degree days, base 50°F
3,731
Growing degree days, base 55°F
2,672
Growing degree days, base 60°F
1,762

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January953017
February776022
March625582
April29731242
May12486431
June17196629
July1291755
August3256718
September60121512
October30319224
November575274
December836026

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 21.9 km from Wayne 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 USC00462522 (Dunlow 1 Sw). Public domain.