Henderson climate

Henderson Frost Dates and Growing Season

NOAA 1991-2020 normals for Savannah Intl AP, 14.3 km from Henderson, elevation 46 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Savannah Intl AP. 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 2 and the first fall freeze around November 30, a growing season of about 270 days.

Median at 36°F
last March 19, first November 16
Median at 32°F
last March 2, first November 30
Median at 28°F
last February 13, first December 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 6Mar 31Mar 27Mar 23Mar 19Mar 16Mar 12Mar 6Feb 26
32°FMar 25Mar 17Mar 12Mar 6Mar 2Feb 26Feb 21Feb 13Feb 4
28°FMar 13Mar 3Feb 26Feb 20Feb 13Feb 7Feb 2Jan 26Jan 15
24°FFeb 28Feb 16Feb 6Feb 2Jan 28Jan 22Jan 14Jan 7Dec 29
20°FFeb 13Feb 4Jan 30Jan 22Jan 16Jan 11Jan 7Jan 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 1Nov 6Nov 9Nov 12Nov 16Nov 19Nov 23Nov 28Dec 4
32°FNov 11Nov 17Nov 21Nov 25Nov 30Dec 3Dec 8Dec 16Dec 28
28°FNov 24Dec 1Dec 6Dec 13Dec 22Dec 29Jan 2Jan 7Jan 17
24°FDec 7Dec 16Dec 25Jan 1Jan 4Jan 9Jan 15Jan 22Feb 4
20°FDec 21Jan 1Jan 3Jan 8Jan 12Jan 17Jan 25Jan 31Feb 7
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°F270260253247242238232226218
32°F304291283277270265260253243
28°F339329318309304298289281267
24°F365365355346338332325314303
20°F365365365365365365362349334
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
78% of years
20°F or colder
32% of years
16°F or colder
4% 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
1,675
Cooling degree days, base 65°F
2,596
Growing degree days, base 40°F
10,076
Growing degree days, base 45°F
8,321
Growing degree days, base 50°F
6,657
Growing degree days, base 55°F
5,137
Growing degree days, base 60°F
3,778

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January4507127
February32012162
March19641326
April63114502
May7287746
June0455904
July05581,023
August0529994
September1382831
October46164584
November21336290
December37912169

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 14.3 km from Henderson. 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 USW00003822 (Savannah Intl AP). Public domain.