Hanover climate

Hanover Frost Dates and Growing Season

NOAA 1991-2020 normals for Newark Wtr Wks, 12.9 km from Hanover, elevation 835 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Newark Wtr Wks. 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 9, first October 4
Median at 32°F
last April 29, first October 16
Median at 28°F
last April 19, first October 27

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 25May 20May 16May 12May 9May 6May 2Apr 29Apr 24
32°FMay 17May 10May 5May 1Apr 29Apr 26Apr 24Apr 21Apr 17
28°FMay 3Apr 29Apr 25Apr 22Apr 19Apr 17Apr 13Apr 8Apr 3
24°FApr 20Apr 16Apr 11Apr 7Apr 5Apr 2Mar 31Mar 27Mar 22
20°FApr 8Apr 3Mar 31Mar 29Mar 25Mar 22Mar 19Mar 15Mar 9
16°FMar 29Mar 24Mar 21Mar 17Mar 14Mar 10Mar 7Mar 2Feb 24

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 9Oct 12Oct 16
32°FOct 1Oct 6Oct 10Oct 13Oct 16Oct 18Oct 21Oct 23Oct 28
28°FOct 13Oct 17Oct 21Oct 24Oct 27Oct 30Nov 1Nov 3Nov 9
24°FOct 25Oct 31Nov 2Nov 4Nov 7Nov 10Nov 13Nov 17Nov 22
20°FNov 3Nov 9Nov 12Nov 15Nov 19Nov 22Nov 27Dec 1Dec 6
16°FNov 12Nov 18Nov 23Nov 28Dec 1Dec 4Dec 8Dec 14Dec 22

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°F165160155151146142138133127
32°F186179174170167164160155148
28°F208203198192189185180176169
24°F236229224220216212207203196
20°F263255249245240235230224218
16°F288279273267262257252246238

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
5,921
Cooling degree days, base 65°F
722
Growing degree days, base 40°F
5,218
Growing degree days, base 45°F
4,033
Growing degree days, base 50°F
2,991
Growing degree days, base 55°F
2,090
Growing degree days, base 60°F
1,331

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,16903
February99003
March820026
April4565114
May19647329
June33156573
July4239701
August11195649
September10471420
October4048143
November717026
December1,01705

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 12.9 km from Hanover. 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 USC00335747 (Newark Wtr Wks). Public domain.