Pocahontas County climate

Pocahontas County Frost Dates and Growing Season

NOAA 1991-2020 normals for Snowshoe, 7.5 km from Pocahontas County, elevation 4847 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Snowshoe. 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 May 12 and the first fall freeze around October 7, a growing season of about 147 days.

Median at 36°F
last May 22, first September 29
Median at 32°F
last May 12, first October 7
Median at 28°F
last May 2, first October 17

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°FJun 4Jun 1May 29May 25May 22May 18May 14May 10May 5
32°FMay 29May 23May 19May 15May 12May 9May 5May 2Apr 26
28°FMay 20May 13May 10May 6May 2Apr 30Apr 27Apr 23Apr 18
24°FMay 12May 4Apr 30Apr 28Apr 24Apr 21Apr 17Apr 14Apr 10
20°FMay 1Apr 24Apr 20Apr 17Apr 14Apr 11Apr 7Apr 4Mar 31
16°FApr 21Apr 15Apr 10Apr 7Apr 4Apr 1Mar 29Mar 25Mar 19

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 15Sep 19Sep 23Sep 26Sep 29Oct 1Oct 3Oct 6Oct 10
32°FSep 24Sep 28Oct 1Oct 5Oct 7Oct 10Oct 12Oct 15Oct 19
28°FOct 4Oct 8Oct 12Oct 14Oct 17Oct 19Oct 21Oct 24Oct 28
24°FOct 13Oct 16Oct 20Oct 22Oct 25Oct 28Oct 31Nov 2Nov 8
20°FOct 22Oct 27Oct 30Nov 1Nov 3Nov 5Nov 8Nov 12Nov 18
16°FOct 31Nov 3Nov 5Nov 8Nov 11Nov 15Nov 19Nov 23Dec 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°F149142136132128124119114106
32°F166161156152147143139134127
28°F185178173169165161157152144
24°F204196191187184180175169162
20°F224217212207203198193188180
16°F246237231226222218213207199

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
8,018
Cooling degree days, base 65°F
57
Growing degree days, base 40°F
3,362
Growing degree days, base 45°F
2,357
Growing degree days, base 50°F
1,502
Growing degree days, base 55°F
805
Growing degree days, base 60°F
308

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,33100
February1,15201
March1,05906
April690042
May4222138
June1909278
July9824391
August12018363
September2665214
October599061
November91208
December1,18001

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 7.5 km from Pocahontas County. 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 USC00468308 (Snowshoe). Public domain.