Hanover climate

Hanover Frost Dates and Growing Season

NOAA 1991-2020 normals for Elizabeth, 8 km from Hanover, elevation 675 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Elizabeth. 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 1 and the first fall freeze around October 9, a growing season of about 160 days.

Median at 36°F
last May 11, first September 30
Median at 32°F
last May 1, first October 9
Median at 28°F
last April 20, first October 19

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 26May 22May 17May 14May 11May 8May 5May 1Apr 27
32°FMay 17May 11May 7May 4May 1Apr 29Apr 25Apr 22Apr 17
28°FMay 6May 1Apr 27Apr 23Apr 20Apr 17Apr 13Apr 10Apr 5
24°FApr 24Apr 17Apr 13Apr 10Apr 7Apr 5Apr 2Mar 30Mar 23
20°FApr 12Apr 6Apr 3Apr 1Mar 28Mar 24Mar 20Mar 15Mar 9
16°FApr 1Mar 28Mar 23Mar 19Mar 15Mar 12Mar 8Mar 5Mar 1

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 17Sep 21Sep 24Sep 27Sep 30Oct 2Oct 5Oct 7Oct 12
32°FSep 25Sep 29Oct 3Oct 6Oct 9Oct 11Oct 15Oct 18Oct 23
28°FOct 4Oct 10Oct 14Oct 16Oct 19Oct 22Oct 24Oct 28Nov 1
24°FOct 17Oct 21Oct 25Oct 28Oct 30Nov 1Nov 4Nov 9Nov 15
20°FOct 29Nov 1Nov 3Nov 6Nov 10Nov 13Nov 17Nov 21Nov 26
16°FNov 3Nov 9Nov 14Nov 17Nov 20Nov 24Nov 27Dec 1Dec 6

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°F159153148145141137133128121
32°F181173169164160157152146139
28°F204196191187183178173168160
24°F226218212208205201196191182
20°F250242236231227223218213207
16°F270262257252247242238233224

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
7,003
Cooling degree days, base 65°F
677
Growing degree days, base 40°F
4,818
Growing degree days, base 45°F
3,736
Growing degree days, base 50°F
2,781
Growing degree days, base 55°F
1,953
Growing degree days, base 60°F
1,247

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,42000
February1,16101
March917118
April534378
May23942290
June39151563
July7232690
August18176623
September14664376
October4578126
November834016
December1,23201

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 8 km from Hanover. 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 USC00112745 (Elizabeth). Public domain.