Romney climate

Romney Frost Dates and Growing Season

NOAA 1991-2020 normals for Romney 1 Sw, 1.3 km from Romney, elevation 720 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Romney 1 Sw. 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 26 and the first fall freeze around October 18, a growing season of about 172 days.

Median at 36°F
last May 8, first October 8
Median at 32°F
last April 26, first October 18
Median at 28°F
last April 12, first October 30

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 15May 11May 8May 4May 1Apr 28Apr 24
32°FMay 14May 9May 4Apr 30Apr 26Apr 24Apr 21Apr 17Apr 12
28°FMay 1Apr 24Apr 19Apr 16Apr 12Apr 10Apr 7Apr 3Mar 30
24°FApr 14Apr 9Apr 6Apr 3Mar 31Mar 30Mar 26Mar 22Mar 17
20°FApr 3Mar 31Mar 27Mar 22Mar 19Mar 17Mar 13Mar 7Mar 2
16°FMar 23Mar 19Mar 15Mar 11Mar 6Mar 3Feb 28Feb 22Feb 15

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 25Sep 30Oct 2Oct 5Oct 8Oct 10Oct 13Oct 17Oct 22
32°FOct 5Oct 9Oct 12Oct 15Oct 18Oct 21Oct 24Oct 28Nov 1
28°FOct 14Oct 19Oct 22Oct 26Oct 30Nov 1Nov 3Nov 6Nov 10
24°FOct 24Oct 30Nov 1Nov 4Nov 6Nov 9Nov 12Nov 16Nov 21
20°FNov 1Nov 7Nov 11Nov 14Nov 17Nov 21Nov 26Dec 1Dec 5
16°FNov 12Nov 18Nov 23Nov 29Dec 2Dec 6Dec 12Dec 19Dec 25

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°F171165159155151146142137129
32°F194186181176172168164157149
28°F217211206202197193188181173
24°F241235229225220217213208201
20°F270261255249245240236230222
16°F300291284278272267260253245

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
5,326
Cooling degree days, base 65°F
852
Growing degree days, base 40°F
5,592
Growing degree days, base 45°F
4,354
Growing degree days, base 50°F
3,258
Growing degree days, base 55°F
2,310
Growing degree days, base 60°F
1,507

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,06904
February87905
March737136
April39410148
May16256366
June28167590
July2275738
August8238695
September8193463
October35213176
November666034
December94705

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 1.3 km from Romney. 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 USC00467730 (Romney 1 Sw). Public domain.