Dillsboro climate

Dillsboro Frost Dates and Growing Season

NOAA 1991-2020 normals for Warsaw Markland Dam, 28.2 km from Dillsboro, elevation 451 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Warsaw Markland Dam. 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 17 and the first fall freeze around October 29, a growing season of about 194 days.

Median at 36°F
last April 28, first October 18
Median at 32°F
last April 17, first October 29
Median at 28°F
last April 4, first November 7

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 15May 8May 4Apr 30Apr 28Apr 25Apr 21Apr 18Apr 13
32°FMay 4Apr 29Apr 25Apr 21Apr 17Apr 15Apr 11Apr 7Apr 2
28°FApr 23Apr 15Apr 12Apr 7Apr 4Apr 1Mar 29Mar 24Mar 18
24°FApr 8Apr 2Mar 29Mar 25Mar 22Mar 19Mar 15Mar 11Mar 3
20°FMar 26Mar 21Mar 17Mar 14Mar 10Mar 6Mar 2Feb 26Feb 17
16°FMar 16Mar 11Mar 5Mar 2Feb 26Feb 21Feb 14Feb 8Feb 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 6Oct 11Oct 13Oct 16Oct 18Oct 21Oct 24Oct 26Oct 31
32°FOct 15Oct 19Oct 22Oct 26Oct 29Oct 31Nov 2Nov 5Nov 10
28°FOct 26Nov 1Nov 2Nov 4Nov 7Nov 10Nov 13Nov 16Nov 21
24°FNov 4Nov 8Nov 11Nov 14Nov 17Nov 20Nov 24Nov 29Dec 4
20°FNov 11Nov 17Nov 22Nov 26Nov 30Dec 3Dec 7Dec 14Dec 23
16°FNov 20Nov 29Dec 3Dec 8Dec 14Dec 20Dec 24Dec 29Jan 5

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°F192186181177173169164159152
32°F214207202198194190186180170
28°F239232227221217214209204197
24°F266257250246241237232226219
20°F295285277271265259254249240
16°F320310303298291285278271260

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
4,695
Cooling degree days, base 65°F
1,155
Growing degree days, base 40°F
6,313
Growing degree days, base 45°F
4,982
Growing degree days, base 50°F
3,803
Growing degree days, base 55°F
2,779
Growing degree days, base 60°F
1,897

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January99905
February81509
March651353
April31813194
May10984443
June11230669
July1345809
August2313777
September45143549
October27823238
November598148
December871010

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 28.2 km from Dillsboro. 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 USC00158446 (Warsaw Markland Dam). Public domain.