Sanford climate

Sanford Frost Dates and Growing Season

NOAA 1991-2020 normals for Midland, 16.1 km from Sanford, elevation 640 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Midland. 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 April 29 and the first fall freeze around October 16, a growing season of about 167 days.

Median at 36°F
last May 10, first October 4
Median at 32°F
last April 29, first October 16
Median at 28°F
last April 18, first October 31

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°FMay 28May 23May 18May 14May 10May 7May 3Apr 30Apr 26
32°FMay 16May 10May 5May 2Apr 29Apr 27Apr 24Apr 20Apr 16
28°FMay 2Apr 28Apr 23Apr 21Apr 18Apr 15Apr 13Apr 9Apr 4
24°FApr 20Apr 16Apr 13Apr 9Apr 6Apr 4Apr 1Mar 30Mar 24
20°FApr 11Apr 6Apr 3Apr 1Mar 30Mar 27Mar 22Mar 19Mar 14
16°FApr 3Mar 30Mar 27Mar 23Mar 19Mar 17Mar 14Mar 10Mar 4

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°FSep 21Sep 25Sep 29Oct 1Oct 4Oct 6Oct 10Oct 13Oct 18
32°FOct 1Oct 5Oct 9Oct 13Oct 16Oct 20Oct 23Oct 27Nov 1
28°FOct 15Oct 21Oct 25Oct 28Oct 31Nov 2Nov 5Nov 9Nov 15
24°FOct 30Nov 2Nov 5Nov 8Nov 12Nov 14Nov 18Nov 22Nov 27
20°FNov 7Nov 13Nov 17Nov 20Nov 23Nov 27Nov 30Dec 3Dec 9
16°FNov 17Nov 22Nov 26Dec 1Dec 4Dec 7Dec 11Dec 16Dec 23

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°F163157152148144140136130124
32°F190182176171167162158154147
28°F216209203199195190186180171
24°F241234228223219215211206199
20°F263255248244240235231225218
16°F282275269264259255249244236

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
100% of years
16°F or colder
100% 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
6,797
Cooling degree days, base 65°F
630
Growing degree days, base 40°F
4,708
Growing degree days, base 45°F
3,633
Growing degree days, base 50°F
2,691
Growing degree days, base 55°F
1,871
Growing degree days, base 60°F
1,178

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,30300
February1,12800
March962113
April577364
May25637271
June53131528
July10220676
August18170617
September13662382
October4456123
November788016
December1,12201

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 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 USC00205434 (Midland). Public domain.