Carolina climate

Carolina Frost Dates and Growing Season

NOAA 1991-2020 normals for Kingston, 10.7 km from Carolina, elevation 117 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Kingston. 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 May 3 and the first fall freeze around October 8, a growing season of about 159 days.

Median at 36°F
last May 14, first October 1
Median at 32°F
last May 3, first October 8
Median at 28°F
last April 20, first October 20

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 27May 23May 20May 17May 14May 11May 8May 4Apr 30
32°FMay 16May 11May 8May 5May 3Apr 30Apr 28Apr 25Apr 21
28°FMay 5Apr 30Apr 26Apr 23Apr 20Apr 17Apr 14Apr 10Apr 6
24°FApr 21Apr 14Apr 10Apr 7Apr 4Apr 2Mar 30Mar 27Mar 21
20°FApr 4Mar 31Mar 29Mar 26Mar 22Mar 19Mar 15Mar 12Mar 7
16°FMar 27Mar 20Mar 17Mar 14Mar 11Mar 8Mar 4Mar 1Feb 24

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 17Sep 23Sep 27Sep 29Oct 1Oct 2Oct 4Oct 7Oct 11
32°FSep 30Oct 2Oct 4Oct 6Oct 8Oct 11Oct 14Oct 18Oct 23
28°FOct 5Oct 10Oct 14Oct 17Oct 20Oct 23Oct 27Oct 30Nov 4
24°FOct 16Oct 21Oct 25Oct 29Nov 1Nov 4Nov 7Nov 11Nov 17
20°FOct 29Nov 3Nov 8Nov 12Nov 15Nov 19Nov 23Nov 29Dec 4
16°FNov 13Nov 18Nov 23Nov 27Dec 1Dec 4Dec 7Dec 13Dec 22

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°F156150145141138135130126120
32°F179172167162159155152148142
28°F203197192187183179174169162
24°F230223218213209205201196187
20°F263254248243238232228222214
16°F287279273268264259255249240

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
5,572
Cooling degree days, base 65°F
658
Growing degree days, base 40°F
5,147
Growing degree days, base 45°F
3,921
Growing degree days, base 50°F
2,865
Growing degree days, base 55°F
1,972
Growing degree days, base 60°F
1,235

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,06902
February91701
March81509
April500266
May23220262
June49107509
July4238699
August9205662
September9078440
October3569169
November626041
December90707

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 10.7 km from Carolina. 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 USC00374266 (Kingston). Public domain.