New Hope climate

New Hope Frost Dates and Growing Season

NOAA 1991-2020 normals for Columbus, 5.4 km from New Hope, elevation 145 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Columbus. 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 March 13 and the first fall freeze around November 12, a growing season of about 244 days.

Median at 36°F
last March 30, first November 2
Median at 32°F
last March 13, first November 12
Median at 28°F
last February 26, first November 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°FApr 16Apr 9Apr 5Apr 2Mar 30Mar 26Mar 22Mar 17Mar 9
32°FApr 2Mar 27Mar 22Mar 17Mar 13Mar 8Mar 3Feb 27Feb 19
28°FMar 17Mar 10Mar 5Mar 1Feb 26Feb 21Feb 15Feb 7Jan 30
24°FMar 6Feb 27Feb 22Feb 12Feb 7Feb 1Jan 29Jan 22Jan 10
20°FFeb 24Feb 10Feb 3Jan 31Jan 27Jan 20Jan 13Jan 5Dec 27
16°FFeb 8Feb 1Jan 29Jan 24Jan 19Jan 13Jan 9Jan 5Dec 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°FOct 19Oct 24Oct 28Nov 1Nov 2Nov 5Nov 7Nov 11Nov 17
32°FOct 30Nov 2Nov 6Nov 8Nov 12Nov 16Nov 19Nov 24Dec 1
28°FNov 7Nov 12Nov 17Nov 23Nov 27Dec 1Dec 4Dec 10Dec 23
24°FNov 20Nov 28Dec 2Dec 8Dec 15Dec 23Dec 30Jan 4Jan 14
20°FDec 3Dec 15Dec 23Dec 29Jan 2Jan 6Jan 11Jan 19Jan 31
16°FDec 16Dec 28Jan 1Jan 5Jan 10Jan 14Jan 18Jan 26Feb 1

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°F244235230224218213208203197
32°F271262255249244239234227219
28°F308297288279273267260252244
24°F346335328319311304295287275
20°F365365359349341336329319307
16°F365365365365365364355343333

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
97% of years
20°F or colder
75% of years
16°F or colder
39% 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
2,326
Cooling degree days, base 65°F
2,494
Growing degree days, base 40°F
9,398
Growing degree days, base 45°F
7,734
Growing degree days, base 50°F
6,198
Growing degree days, base 55°F
4,808
Growing degree days, base 60°F
3,571

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January598374
February4238112
March25437280
April89102466
May12266719
June0454904
July05661,031
August05471,012
September3363810
October90126504
November32917190
December529595

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 5.4 km from New Hope. 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 USC00221880 (Columbus). Public domain.