Buncombe County climate

Buncombe County Frost Dates and Growing Season

NOAA 1991-2020 normals for Asheville, 3 km from Buncombe County, elevation 2238 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Asheville. 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 6 and the first fall freeze around October 31, a growing season of about 205 days.

Median at 36°F
last April 20, first October 21
Median at 32°F
last April 6, first October 31
Median at 28°F
last March 26, first November 10

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 9May 3Apr 29Apr 24Apr 20Apr 16Apr 13Apr 10Apr 5
32°FApr 24Apr 17Apr 13Apr 10Apr 6Apr 2Mar 31Mar 27Mar 20
28°FApr 10Apr 5Apr 2Mar 30Mar 26Mar 22Mar 18Mar 13Mar 7
24°FMar 31Mar 24Mar 20Mar 16Mar 12Mar 9Mar 5Feb 28Feb 19
20°FMar 20Mar 14Mar 8Mar 3Feb 27Feb 21Feb 14Feb 7Jan 30
16°FMar 10Mar 2Feb 24Feb 16Feb 8Feb 3Jan 30Jan 22Jan 11

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 9Oct 13Oct 16Oct 19Oct 21Oct 24Oct 26Oct 29Nov 2
32°FOct 17Oct 23Oct 26Oct 28Oct 31Nov 2Nov 4Nov 7Nov 13
28°FOct 28Nov 1Nov 4Nov 6Nov 10Nov 13Nov 16Nov 21Nov 28
24°FNov 6Nov 12Nov 15Nov 19Nov 23Nov 27Dec 1Dec 6Dec 15
20°FNov 17Nov 24Nov 29Dec 3Dec 7Dec 14Dec 20Dec 27Jan 3
16°FDec 1Dec 9Dec 17Dec 23Dec 28Jan 2Jan 7Jan 13Jan 24

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°F201196191186182178174168161
32°F226218214210205201197192185
28°F255246239235230225220215207
24°F285276268262257251245239231
20°F319309300294288281274266254
16°F349336329322315308301294282

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
98% 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
3,879
Cooling degree days, base 65°F
1,092
Growing degree days, base 40°F
6,739
Growing degree days, base 45°F
5,276
Growing degree days, base 50°F
3,977
Growing degree days, base 55°F
2,850
Growing degree days, base 60°F
1,889

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January831016
February654024
March520297
April25121252
May8488472
June9217658
July0320784
August1286750
September35136551
October23920270
November516176
December741028

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 3 km from Buncombe 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 USW00013872 (Asheville). Public domain.