Yemassee climate

Yemassee Frost Dates and Growing Season

NOAA 1991-2020 normals for Yemassee 1 N, 1.3 km from Yemassee, elevation 44 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Yemassee 1 N. 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 March 23 and the first fall freeze around November 6, a growing season of about 233 days.

Median at 36°F
last April 7, first October 29
Median at 32°F
last March 23, first November 6
Median at 28°F
last March 7, first November 22

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 23Apr 18Apr 13Apr 10Apr 7Apr 4Apr 1Mar 28Mar 19
32°FApr 11Apr 4Mar 30Mar 27Mar 23Mar 20Mar 15Mar 8Feb 28
28°FMar 27Mar 22Mar 17Mar 12Mar 7Mar 2Feb 26Feb 20Feb 10
24°FMar 17Mar 9Mar 2Feb 26Feb 18Feb 9Feb 2Jan 28Jan 17
20°FMar 2Feb 20Feb 9Feb 1Jan 28Jan 22Jan 15Jan 5Dec 28
16°FFeb 19Feb 5Jan 29Jan 24Jan 17Jan 10Jan 5Dec 31Dec 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°FOct 16Oct 21Oct 24Oct 26Oct 29Nov 1Nov 3Nov 6Nov 13
32°FOct 25Oct 30Nov 1Nov 4Nov 6Nov 10Nov 15Nov 20Dec 1
28°FNov 3Nov 8Nov 13Nov 17Nov 22Nov 27Dec 1Dec 6Dec 16
24°FNov 15Nov 23Nov 29Dec 3Dec 8Dec 14Dec 22Dec 31Jan 7
20°FDec 2Dec 8Dec 15Dec 21Dec 28Jan 1Jan 6Jan 14Jan 29
16°FDec 11Dec 22Dec 28Jan 1Jan 5Jan 9Jan 16Jan 26Feb 3

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°F231223216212207203198192186
32°F263253244239233227222217208
28°F297283276268262256249241233
24°F337325313304297291283273260
20°F365360349340333325314304293
16°F365365365365365356347336325

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
99% of years
20°F or colder
87% of years
16°F or colder
50% 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
2,193
Cooling degree days, base 65°F
1,965
Growing degree days, base 40°F
8,966
Growing degree days, base 45°F
7,262
Growing degree days, base 50°F
5,685
Growing degree days, base 55°F
4,265
Growing degree days, base 60°F
3,018

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January538289
February3884116
March27320247
April10771416
May18210657
June1368817
July0467931
August0434899
September5278723
October9390466
November29719212
December4753110

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 1.3 km from Yemassee. 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 USC00389469 (Yemassee 1 N). Public domain.