Summers County climate

Summers County Frost Dates and Growing Season

NOAA 1991-2020 normals for Bluestone Lake, 2.7 km from Summers County, elevation 1390 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Bluestone Lake. 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 10 and the first fall freeze around October 30, a growing season of about 200 days.

Median at 36°F
last April 27, first October 21
Median at 32°F
last April 10, first October 30
Median at 28°F
last March 30, 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 14May 8May 4Apr 30Apr 27Apr 23Apr 20Apr 17Apr 12
32°FMay 3Apr 23Apr 18Apr 14Apr 10Apr 7Apr 4Apr 1Mar 28
28°FApr 10Apr 6Apr 3Apr 1Mar 30Mar 27Mar 23Mar 18Mar 13
24°FApr 2Mar 29Mar 25Mar 21Mar 18Mar 14Mar 10Mar 5Feb 27
20°FMar 23Mar 18Mar 13Mar 8Mar 5Mar 1Feb 26Feb 18Feb 9
16°FMar 15Mar 7Mar 3Feb 28Feb 23Feb 16Feb 10Feb 4Jan 27

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 9Oct 13Oct 16Oct 19Oct 21Oct 24Oct 26Oct 28Nov 1
32°FOct 17Oct 22Oct 25Oct 28Oct 30Nov 1Nov 2Nov 5Nov 10
28°FOct 27Oct 31Nov 2Nov 5Nov 8Nov 11Nov 14Nov 19Nov 24
24°FNov 4Nov 9Nov 13Nov 17Nov 20Nov 24Nov 28Dec 1Dec 7
20°FNov 14Nov 22Nov 26Nov 30Dec 2Dec 6Dec 11Dec 18Dec 25
16°FNov 29Dec 4Dec 9Dec 14Dec 19Dec 25Dec 30Jan 4Jan 14

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°F196190185181177174170165158
32°F219213208204200196192187178
28°F246238231227224220215211205
24°F275267261255249243238232226
20°F305294287281275269263257248
16°F332321312305299293286280270

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
99% 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
4,657
Cooling degree days, base 65°F
1,028
Growing degree days, base 40°F
6,166
Growing degree days, base 45°F
4,840
Growing degree days, base 50°F
3,664
Growing degree days, base 55°F
2,639
Growing degree days, base 60°F
1,758

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January97604
February78505
March637155
April31912194
May12173421
June15208643
July1306770
August1280744
September43135542
October28213226
November599052
December87708

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 2.7 km from Summers 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 USC00460939 (Bluestone Lake). Public domain.