Palm Beach County Frost Dates and Growing Season

NOAA 1991-2020 normals for Belle Glade, 23.9 km from Palm Beach County, elevation 20 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Belle Glade. A median date has an even chance of a later freeze in spring, or an earlier one in fall.

A freeze (32°F or colder) happens in only 48 percent of years at Belle Glade, so there is no typical freeze season.

Median at 36°F: last February 5, first January 10
Median at 32°F: last January 27, first January 16
Median at 28°F: last January 25, first January 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.

Threshold	10%	20%	30%	40%	50%	60%	70%	80%	90%
36°F	Feb 28	Feb 22	Feb 15	Feb 10	Feb 5	Jan 31	Jan 24	Jan 16	Jan 6
32°F	Feb 18	Feb 9	Feb 4	Feb 1	Jan 27	Jan 20	Jan 13	Jan 7	Jan 1
28°F	Feb 13	Feb 5	Feb 1	Jan 30	Jan 25	Jan 22	Jan 12	Jan 5	Dec 31
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.

Threshold	10%	20%	30%	40%	50%	60%	70%	80%	90%
36°F	Dec 16	Dec 26	Jan 1	Jan 5	Jan 10	Jan 15	Jan 21	Jan 28	Feb 5
32°F	Dec 26	Jan 1	Jan 5	Jan 9	Jan 16	Jan 22	Jan 29	Feb 3	Feb 10
28°F	Dec 28	Jan 3	Jan 6	Jan 13	Jan 22	Jan 27	Jan 31	Feb 3	Feb 10
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.

Threshold	10%	20%	30%	40%	50%	60%	70%	80%	90%
36°F	365	355	345	335	329	323	316	309	301
32°F	365	365	365	365	365	356	341	332	322
28°F	365	365	365	365	365	365	365	365	342
24°F	365	365	365	365	365	365	365	365	365
20°F	365	365	365	365	365	365	365	365	365
16°F	365	365	365	365	365	365	365	365	365

How often it gets that cold

The share of years with at least one night at or below each temperature.

36°F or colder: 83% of years
32°F or colder: 48% of years
28°F or colder: 15% of years
24°F or colder: 1% 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: 294
Cooling degree days, base 65°F: 3,711
Growing degree days, base 40°F: 12,542
Growing degree days, base 45°F: 10,719
Growing degree days, base 50°F: 8,901
Growing degree days, base 55°F: 7,102
Growing degree days, base 60°F: 5,358

Growing degree days by month, base 50°F

Heating and cooling by month

Month	Heating DD	Cooling DD	Growing DD 50
January	110	74	435
February	67	92	447
March	30	163	598
April	4	252	698
May	1	390	854
June	0	477	927
July	0	538	1,003
August	0	543	1,008
September	0	492	942
October	1	382	846
November	17	190	623
December	65	119	521

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

Sources

NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USC00080611 (Belle Glade). Public domain.