Flanders climate

Flanders Frost Dates and Growing Season

NOAA 1991-2020 normals for Westhamptn Gabreski AP, 6.7 km from Flanders, elevation 67 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Westhamptn Gabreski AP. 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 May 7 and the first fall freeze around October 14, a growing season of about 160 days.

Median at 36°F
last May 20, first October 4
Median at 32°F
last May 7, first October 14
Median at 28°F
last April 27, first October 26

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°FJun 2May 29May 25May 22May 20May 17May 13May 9May 3
32°FMay 23May 17May 14May 10May 7May 4May 1Apr 28Apr 23
28°FMay 12May 7May 3Apr 30Apr 27Apr 23Apr 20Apr 16Apr 10
24°FApr 28Apr 23Apr 19Apr 15Apr 12Apr 8Apr 4Apr 1Mar 28
20°FApr 16Apr 11Apr 5Apr 2Mar 30Mar 27Mar 23Mar 18Mar 12
16°FApr 2Mar 29Mar 24Mar 20Mar 16Mar 13Mar 9Mar 5Feb 28

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 23Sep 28Sep 30Oct 2Oct 4Oct 6Oct 9Oct 12Oct 16
32°FOct 2Oct 5Oct 8Oct 11Oct 14Oct 17Oct 19Oct 24Oct 31
28°FOct 10Oct 15Oct 18Oct 22Oct 26Oct 29Nov 1Nov 4Nov 9
24°FOct 20Oct 26Oct 31Nov 2Nov 5Nov 8Nov 12Nov 16Nov 22
20°FNov 1Nov 6Nov 11Nov 14Nov 17Nov 20Nov 24Nov 30Dec 4
16°FNov 13Nov 19Nov 23Nov 27Dec 1Dec 4Dec 7Dec 12Dec 19

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°F157151145141137134130125119
32°F181174168163160156152146139
28°F205197192188184180175169161
24°F232223217212209204199194184
20°F256249243238233229223218211
16°F284277271265260255249244238

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
5,924
Cooling degree days, base 65°F
578
Growing degree days, base 40°F
4,842
Growing degree days, base 45°F
3,654
Growing degree days, base 50°F
2,648
Growing degree days, base 55°F
1,804
Growing degree days, base 60°F
1,112

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,10500
February96200
March86205
April568140
May2919205
June6684468
July7221679
August10191646
September10365414
October3807151
November645033
December92507

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 6.7 km from Flanders. 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 USW00014719 (Westhamptn Gabreski AP). Public domain.