Berkeley Lake climate

Berkeley Lake Frost Dates and Growing Season

NOAA 1991-2020 normals for Atlanta Peachtree AP, 16.1 km from Berkeley Lake, elevation 1002 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Atlanta Peachtree 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 25 and the first fall freeze around November 9, a growing season of about 228 days.

Median at 36°F
last April 7, first October 29
Median at 32°F
last March 25, first November 9
Median at 28°F
last March 12, 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 22Apr 17Apr 14Apr 10Apr 7Apr 4Apr 1Mar 28Mar 21
32°FApr 12Apr 5Apr 1Mar 29Mar 25Mar 22Mar 17Mar 12Mar 5
28°FMar 31Mar 25Mar 20Mar 16Mar 12Mar 7Mar 2Feb 26Feb 18
24°FMar 17Mar 10Mar 5Feb 28Feb 23Feb 17Feb 10Feb 3Jan 26
20°FMar 5Feb 26Feb 17Feb 10Feb 3Jan 30Jan 25Jan 16Jan 7
16°FFeb 23Feb 10Feb 4Jan 31Jan 26Jan 21Jan 16Jan 9Dec 31

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

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°F225218212208205201197191185
32°F253245239233228223218212205
28°F287276268262256252247239229
24°F326313304296289283276267256
20°F356342334328322315308300288
16°F365365362352345338333325313

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
100% of years
20°F or colder
95% of years
16°F or colder
71% 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
2,980
Cooling degree days, base 65°F
1,729
Growing degree days, base 40°F
8,044
Growing degree days, base 45°F
6,457
Growing degree days, base 50°F
5,025
Growing degree days, base 55°F
3,751
Growing degree days, base 60°F
2,654

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January704037
February528156
March3707166
April16039337
May33169601
June0338788
July0454919
August0423888
September10245685
October14648375
November4063120
December622153

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 16.1 km from Berkeley Lake. 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 USW00053863 (Atlanta Peachtree AP). Public domain.