Sharpes Frost Dates and Growing Season

NOAA 1991-2020 normals for Titusville, 22.1 km from Sharpes, elevation 16 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Titusville. 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 25 and the first fall freeze around January 13, a growing season of about 362 days.

Median at 36°F: last February 3, first January 5
Median at 32°F: last January 25, first January 13
Median at 28°F: last January 22, 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.

Threshold	10%	20%	30%	40%	50%	60%	70%	80%	90%
36°F	Mar 7	Feb 26	Feb 18	Feb 9	Feb 3	Jan 29	Jan 22	Jan 14	Jan 5
32°F	Feb 24	Feb 12	Feb 4	Jan 31	Jan 25	Jan 21	Jan 14	Jan 9	Dec 31
28°F	Feb 8	Feb 4	Jan 31	Jan 27	Jan 22	Jan 17	Jan 9	Jan 4	Dec 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.

Threshold	10%	20%	30%	40%	50%	60%	70%	80%	90%
36°F	Dec 9	Dec 20	Dec 26	Jan 1	Jan 5	Jan 10	Jan 17	Jan 24	Feb 4
32°F	Dec 23	Dec 30	Jan 4	Jan 8	Jan 13	Jan 20	Jan 26	Feb 1	Feb 10
28°F	Dec 25	Jan 1	Jan 5	Jan 10	Jan 16	Jan 22	Jan 29	Feb 1	Feb 7
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	364	351	341	334	328	320	312	303	292
32°F	365	365	365	365	362	351	341	333	315
28°F	365	365	365	365	365	365	365	365	352
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: 88% of years
32°F or colder: 51% 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: 605
Cooling degree days, base 65°F: 3,275
Growing degree days, base 40°F: 11,796
Growing degree days, base 45°F: 9,979
Growing degree days, base 50°F: 8,182
Growing degree days, base 55°F: 6,437
Growing degree days, base 60°F: 4,787

Growing degree days by month, base 50°F

Heating and cooling by month

Month	Heating DD	Cooling DD	Growing DD 50
January	204	37	318
February	126	51	353
March	70	106	502
April	15	194	629
May	1	356	820
June	0	459	909
July	0	530	995
August	0	529	994
September	0	465	915
October	5	332	792
November	43	145	552
December	141	72	404

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 22.1 km from Sharpes. 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 USC00088942 (Titusville). Public domain.