Ranson climate

Ranson Frost Dates and Growing Season

NOAA 1991-2020 normals for Martinsburg E Wv Rgnl AP, 15.9 km from Ranson, elevation 534 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Martinsburg E Wv Rgnl AP. 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 20 and the first fall freeze around October 22, a growing season of about 183 days.

Median at 36°F
last May 5, first October 11
Median at 32°F
last April 20, first October 22
Median at 28°F
last April 4, first November 1

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 22May 17May 12May 8May 5May 1Apr 28Apr 23Apr 17
32°FMay 12May 4Apr 30Apr 24Apr 20Apr 17Apr 13Apr 9Apr 3
28°FApr 22Apr 15Apr 10Apr 7Apr 4Apr 2Mar 30Mar 27Mar 22
24°FApr 6Apr 2Mar 30Mar 27Mar 24Mar 21Mar 17Mar 13Mar 8
20°FMar 28Mar 23Mar 19Mar 16Mar 12Mar 9Mar 6Mar 2Feb 25
16°FMar 19Mar 13Mar 9Mar 5Mar 2Feb 27Feb 24Feb 16Feb 9

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 29Oct 2Oct 5Oct 8Oct 11Oct 14Oct 17Oct 20Oct 25
32°FOct 7Oct 11Oct 15Oct 19Oct 22Oct 25Oct 28Oct 31Nov 4
28°FOct 16Oct 23Oct 27Oct 30Nov 1Nov 3Nov 6Nov 10Nov 14
24°FOct 28Nov 2Nov 5Nov 9Nov 12Nov 15Nov 18Nov 22Nov 28
20°FNov 8Nov 14Nov 18Nov 21Nov 26Dec 1Dec 4Dec 8Dec 15
16°FNov 20Nov 29Dec 3Dec 8Dec 12Dec 16Dec 21Dec 25Jan 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°F180173168163158154150144136
32°F205197192188183178173166158
28°F230223218213208204198192184
24°F254246241237233228223218210
20°F285275268263258253248242234
16°F316305297291285280275268260

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
4,947
Cooling degree days, base 65°F
1,013
Growing degree days, base 40°F
5,967
Growing degree days, base 45°F
4,676
Growing degree days, base 50°F
3,533
Growing degree days, base 55°F
2,543
Growing degree days, base 60°F
1,702

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,01106
February84008
March688142
April35412167
May14164391
June18201633
July0332797
August3274736
September63114502
October31814198
November611044
December901010

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 15.9 km from Ranson. 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 USW00013734 (Martinsburg E Wv Rgnl AP). Public domain.