Hampton climate

Hampton Frost Dates and Growing Season

NOAA 1991-2020 normals for Whitehall, 12.6 km from Hampton, elevation 119 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Whitehall. 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 30 and the first fall freeze around October 12, a growing season of about 164 days.

Median at 36°F
last May 11, first October 1
Median at 32°F
last April 30, first October 12
Median at 28°F
last April 19, first October 24

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 24May 19May 16May 13May 11May 8May 5May 2Apr 29
32°FMay 14May 9May 5May 3Apr 30Apr 28Apr 25Apr 22Apr 18
28°FMay 3Apr 28Apr 24Apr 21Apr 19Apr 16Apr 13Apr 10Apr 6
24°FApr 20Apr 16Apr 13Apr 10Apr 8Apr 5Apr 3Apr 1Mar 29
20°FApr 13Apr 8Apr 4Apr 3Apr 1Mar 30Mar 27Mar 23Mar 18
16°FApr 5Apr 2Mar 31Mar 28Mar 25Mar 22Mar 19Mar 15Mar 11

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 19Sep 23Sep 27Sep 30Oct 1Oct 4Oct 6Oct 10Oct 15
32°FSep 28Oct 1Oct 4Oct 9Oct 12Oct 15Oct 18Oct 21Oct 26
28°FOct 7Oct 14Oct 18Oct 21Oct 24Oct 27Oct 30Nov 2Nov 6
24°FOct 22Oct 26Oct 31Nov 2Nov 4Nov 8Nov 11Nov 15Nov 19
20°FNov 1Nov 5Nov 10Nov 13Nov 16Nov 19Nov 22Nov 26Dec 1
16°FNov 11Nov 17Nov 21Nov 24Nov 27Nov 30Dec 3Dec 6Dec 11

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°F161155150147144140136132125
32°F183176172168164161157151144
28°F207200195192188183179174166
24°F229223219215211208204198191
20°F249242236232229225221215209
16°F267260256252247243239233225

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
6,880
Cooling degree days, base 65°F
674
Growing degree days, base 40°F
4,794
Growing degree days, base 45°F
3,715
Growing degree days, base 50°F
2,765
Growing degree days, base 55°F
1,935
Growing degree days, base 60°F
1,234

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,35800
February1,16900
March1,00006
April558569
May21835301
June47131534
July10239694
August16196645
September13166390
October4463111
November782014
December1,14701

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 12.6 km from Hampton. 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 USC00309389 (Whitehall). Public domain.