Atlantic Beach climate

Atlantic Beach Frost Dates and Growing Season

NOAA 1991-2020 normals for Jacksonville Beach, 5.2 km from Atlantic Beach, elevation 10 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Jacksonville Beach. 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 January 31 and the first fall freeze around January 10, a growing season of about 345 days.

Median at 36°F
last February 9, first January 1
Median at 32°F
last January 31, first January 10
Median at 28°F
last January 24, first January 16

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 10Mar 2Feb 25Feb 16Feb 9Feb 3Jan 30Jan 21Jan 10
32°FMar 2Feb 21Feb 11Feb 3Jan 31Jan 24Jan 17Jan 11Jan 1
28°FFeb 16Feb 6Jan 31Jan 28Jan 24Jan 16Jan 11Jan 4Dec 27
24°F–––––––––
20°F–––––––––
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°FDec 2Dec 8Dec 18Dec 26Jan 1Jan 5Jan 11Jan 17Jan 29
32°FDec 16Dec 25Jan 1Jan 6Jan 10Jan 16Jan 24Jan 31Feb 14
28°FDec 22Dec 31Jan 5Jan 10Jan 16Jan 22Jan 28Jan 31Feb 9
24°F–––––––––
20°F–––––––––
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°F352338332325318309303295284
32°F365365364354345337331317306
28°F365365365365365365363349334
24°F365365365365365365365365365
20°F365365365365365365365365365
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
94% of years
32°F or colder
67% of years
28°F or colder
28% of years
24°F or colder
5% of years
20°F or colder
0% of years
16°F or colder
0% 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
829
Cooling degree days, base 65°F
3,196
Growing degree days, base 40°F
11,496
Growing degree days, base 45°F
9,684
Growing degree days, base 50°F
7,903
Growing degree days, base 55°F
6,197
Growing degree days, base 60°F
4,616

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January26721248
February17731285
March9281457
April19176608
May1360825
June0482932
July05561,021
August05521,017
September0472922
October8309766
November72113492
December19343330

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 5.2 km from Atlantic Beach. 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 USC00084366 (Jacksonville Beach). Public domain.