Apopka climate

Apopka Frost Dates and Growing Season

NOAA 1991-2020 normals for Mt Plymouth 1SSW, 13.9 km from Apopka, elevation 90 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Mt Plymouth 1SSW. 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 24 and the first fall freeze around December 29, a growing season of about 301 days.

Median at 36°F
last March 12, first December 7
Median at 32°F
last February 24, first December 29
Median at 28°F
last February 3, first January 10

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 25Mar 20Mar 16Mar 12Mar 7Mar 2Feb 23Feb 12
32°FMar 20Mar 13Mar 6Mar 1Feb 24Feb 16Feb 7Feb 1Jan 22
28°FMar 6Feb 26Feb 18Feb 10Feb 3Jan 31Jan 24Jan 14Jan 5
24°FFeb 17Feb 9Feb 3Jan 31Jan 28Jan 22Jan 15Jan 9Jan 2
20°FFeb 10Feb 1Jan 31Jan 26Jan 19Jan 13Jan 9Jan 5Dec 29
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 11Nov 20Nov 28Dec 3Dec 7Dec 13Dec 20Dec 28Jan 6
32°FNov 29Dec 6Dec 14Dec 22Dec 29Jan 3Jan 8Jan 16Jan 27
28°FDec 12Dec 26Jan 1Jan 5Jan 10Jan 16Jan 23Jan 31Feb 9
24°FDec 27Jan 2Jan 7Jan 13Jan 18Jan 24Jan 29Feb 4Feb 12
20°FDec 24Jan 2Jan 8Jan 11Jan 16Jan 25Jan 28Feb 1Feb 10
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°F306294287279273265258249238
32°F335325315307301293285277266
28°F365358347337332325315306295
24°F365365365365365359347337329
20°F365365365365365365365365354
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
98% of years
28°F or colder
80% of years
24°F or colder
42% of years
20°F or colder
12% 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
828
Cooling degree days, base 65°F
3,134
Growing degree days, base 40°F
11,438
Growing degree days, base 45°F
9,629
Growing degree days, base 50°F
7,857
Growing degree days, base 55°F
6,159
Growing degree days, base 60°F
4,569

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January25728273
February17753313
March9778450
April23166593
May1344808
June0475925
July05501,015
August05411,006
September0456906
October15277727
November79119492
December18049349

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 13.9 km from Apopka. 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 USC00087228 (Mt Plymouth 1SSW). Public domain.