McClellanville climate

McClellanville Frost Dates and Growing Season

NOAA 1991-2020 normals for Mcclellanville 7 Ne, 11.6 km from McClellanville, elevation 9 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Mcclellanville 7 Ne. 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 February 28 and the first fall freeze around December 1, a growing season of about 277 days.

Median at 36°F
last March 19, first November 15
Median at 32°F
last February 28, first December 1
Median at 28°F
last February 6, first December 25

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°FApr 6Mar 31Mar 27Mar 22Mar 19Mar 15Mar 10Mar 3Feb 24
32°FMar 25Mar 17Mar 12Mar 5Feb 28Feb 24Feb 19Feb 11Feb 1
28°FMar 9Feb 28Feb 21Feb 13Feb 6Feb 1Jan 29Jan 21Jan 11
24°FFeb 24Feb 8Feb 1Jan 29Jan 25Jan 19Jan 14Jan 8Dec 31
20°FFeb 4Jan 30Jan 27Jan 22Jan 17Jan 13Jan 9Jan 2Dec 27
16°F–––––––––

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°FNov 2Nov 6Nov 9Nov 12Nov 15Nov 19Nov 24Nov 30Dec 6
32°FNov 11Nov 17Nov 23Nov 28Dec 1Dec 6Dec 12Dec 21Dec 31
28°FNov 27Dec 3Dec 9Dec 18Dec 25Jan 1Jan 5Jan 12Jan 23
24°FDec 9Dec 20Dec 30Jan 3Jan 7Jan 11Jan 16Jan 21Feb 1
20°FDec 18Dec 30Jan 3Jan 8Jan 11Jan 15Jan 19Jan 24Jan 31
16°F–––––––––

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°F275266256251246240235229220
32°F310300291283277270264256247
28°F347334327320312305297288276
24°F365365361351345338331322308
20°F365365365365365365362348336
16°F365365365365365365365365365

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
98% of years
24°F or colder
72% of years
20°F or colder
34% of years
16°F or colder
7% 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
2,029
Cooling degree days, base 65°F
2,098
Growing degree days, base 40°F
9,245
Growing degree days, base 45°F
7,523
Growing degree days, base 50°F
5,918
Growing degree days, base 55°F
4,468
Growing degree days, base 60°F
3,187

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January5132100
February3953111
March26817244
April9667424
May13218670
June0386836
July0485950
August0454919
September2321769
October64118520
November25421240
December4256136

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 11.6 km from McClellanville. 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 USW00003728 (Mcclellanville 7 Ne). Public domain.