Sanford climate

Sanford Frost Dates and Growing Season

NOAA 1991-2020 normals for Sanford, 1.6 km from Sanford, elevation 12 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Sanford. 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 26 and the first fall freeze around January 12, a growing season of about 359 days.

Median at 36°F
last February 4, first January 6
Median at 32°F
last January 26, first January 12
Median at 28°F
last January 13, first January 11

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 6Feb 26Feb 17Feb 10Feb 4Jan 31Jan 24Jan 16Jan 8
32°FFeb 24Feb 12Feb 6Jan 31Jan 26Jan 19Jan 12Jan 6Dec 31
28°FFeb 6Jan 31Jan 27Jan 19Jan 13Jan 10Jan 6Dec 31Dec 25
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 9Dec 19Dec 27Jan 1Jan 6Jan 11Jan 16Jan 24Feb 6
32°FDec 20Dec 28Jan 2Jan 7Jan 12Jan 18Jan 24Jan 31Feb 10
28°FDec 19Dec 29Jan 3Jan 7Jan 11Jan 14Jan 23Jan 29Feb 5
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°F365354342334328322314306298
32°F365365365365359348338331318
28°F365365365365365365365365348
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
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
609
Cooling degree days, base 65°F
3,408
Growing degree days, base 40°F
11,925
Growing degree days, base 45°F
10,107
Growing degree days, base 50°F
8,309
Growing degree days, base 55°F
6,561
Growing degree days, base 60°F
4,911

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January20338317
February12949347
March68112510
April13208645
May1372835
June0489939
July05581,023
August05601,025
September0486936
October6331791
November47139542
December14267400

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 1.6 km from Sanford. 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 USC00087982 (Sanford). Public domain.