Jasper County climate

Jasper County Frost Dates and Growing Season

NOAA 1991-2020 normals for Beaufort Mcas, 29.5 km from Jasper County, elevation 37 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Beaufort Mcas. 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 3, a growing season of about 279 days.

Median at 36°F
last March 14, first November 18
Median at 32°F
last February 28, first December 3
Median at 28°F
last February 8, first December 27

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°FMar 31Mar 27Mar 22Mar 18Mar 14Mar 11Mar 6Feb 28Feb 22
32°FMar 21Mar 15Mar 10Mar 4Feb 28Feb 24Feb 18Feb 11Feb 2
28°FMar 8Feb 28Feb 22Feb 15Feb 8Feb 3Jan 29Jan 22Jan 8
24°FFeb 27Feb 12Feb 5Jan 31Jan 27Jan 21Jan 14Jan 6Dec 28
20°FFeb 4Jan 30Jan 27Jan 21Jan 16Jan 11Jan 6Jan 2Dec 26
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 4Nov 8Nov 12Nov 15Nov 18Nov 22Nov 26Dec 1Dec 8
32°FNov 14Nov 21Nov 25Nov 30Dec 3Dec 7Dec 14Dec 23Jan 1
28°FDec 1Dec 7Dec 13Dec 21Dec 27Jan 1Jan 5Jan 12Jan 28
24°FDec 12Dec 23Dec 29Jan 2Jan 7Jan 13Jan 19Jan 29Feb 7
20°FDec 23Dec 31Jan 4Jan 8Jan 12Jan 16Jan 21Jan 27Feb 1
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°F278267261254249244239233226
32°F312300292286279274266258248
28°F348336329320312305299291277
24°F365365365358348340333324308
20°F365365365365365365365359344
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
96% of years
24°F or colder
64% of years
20°F or colder
23% of years
16°F or colder
1% 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
1,732
Cooling degree days, base 65°F
2,570
Growing degree days, base 40°F
9,993
Growing degree days, base 45°F
8,240
Growing degree days, base 50°F
6,582
Growing degree days, base 55°F
5,075
Growing degree days, base 60°F
3,733

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January4634115
February3378145
March21033307
April63108496
May6290749
June0453903
July05631,028
August0533998
September1379828
October45155576
November21935283
December38810157

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 29.5 km from Jasper County. Low ground, valleys and open fields freeze earlier and later than a town center or a hillside.

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Sources

NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USW00093831 (Beaufort Mcas). Public domain.