Hunterstown climate

Hunterstown Frost Dates and Growing Season

NOAA 1991-2020 normals for Biglerville, 10 km from Hunterstown, elevation 720 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Biglerville. 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 15 and the first fall freeze around October 27, a growing season of about 194 days.

Median at 36°F
last April 30, first October 15
Median at 32°F
last April 15, first October 27
Median at 28°F
last April 3, first November 8

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 18May 11May 6May 2Apr 30Apr 26Apr 23Apr 19Apr 15
32°FMay 4Apr 29Apr 22Apr 18Apr 15Apr 12Apr 9Apr 5Apr 1
28°FApr 17Apr 12Apr 8Apr 6Apr 3Apr 1Mar 30Mar 26Mar 21
24°FApr 6Apr 2Mar 31Mar 27Mar 23Mar 20Mar 17Mar 13Mar 8
20°FMar 28Mar 23Mar 20Mar 17Mar 14Mar 11Mar 7Mar 3Feb 26
16°FMar 20Mar 16Mar 11Mar 8Mar 5Mar 2Feb 27Feb 21Feb 13

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°FOct 3Oct 6Oct 10Oct 13Oct 15Oct 18Oct 21Oct 24Oct 28
32°FOct 11Oct 15Oct 20Oct 23Oct 27Oct 30Nov 2Nov 5Nov 10
28°FOct 26Oct 31Nov 2Nov 5Nov 8Nov 10Nov 14Nov 18Nov 23
24°FNov 6Nov 11Nov 14Nov 17Nov 20Nov 23Nov 27Dec 1Dec 7
20°FNov 15Nov 20Nov 25Nov 30Dec 3Dec 6Dec 11Dec 17Dec 25
16°FNov 29Dec 4Dec 10Dec 14Dec 19Dec 23Dec 27Jan 1Jan 9

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°F190183178173170165161156148
32°F215207202197194189185179172
28°F237231226221217213210205198
24°F263254249245240236232227220
20°F289279273268263259254249241
16°F310302296292286281276270262

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
5,393
Cooling degree days, base 65°F
966
Growing degree days, base 40°F
5,687
Growing degree days, base 45°F
4,455
Growing degree days, base 50°F
3,368
Growing degree days, base 55°F
2,426
Growing degree days, base 60°F
1,624

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,09002
February92103
March779126
April4169133
May16658363
June26191615
July1317781
August4266727
September72109489
October34015186
November638037
December94106

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 10 km from Hunterstown. 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 USC00360656 (Biglerville). Public domain.