Rowan County climate

Rowan County Frost Dates and Growing Season

NOAA 1991-2020 normals for Cave Run Lake, 12.7 km from Rowan County, elevation 840 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Cave Run 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 17 and the first fall freeze around October 25, a growing season of about 189 days.

Median at 36°F
last April 29, first October 16
Median at 32°F
last April 17, first October 25
Median at 28°F
last April 3, first November 4

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 17May 10May 6May 2Apr 29Apr 25Apr 22Apr 18Apr 13
32°FMay 6Apr 30Apr 24Apr 20Apr 17Apr 14Apr 11Apr 7Apr 2
28°FApr 22Apr 15Apr 10Apr 6Apr 3Mar 31Mar 30Mar 25Mar 19
24°FApr 7Apr 2Mar 31Mar 28Mar 25Mar 20Mar 17Mar 13Mar 6
20°FMar 29Mar 23Mar 19Mar 15Mar 11Mar 7Mar 3Feb 27Feb 20
16°FMar 19Mar 13Mar 7Mar 4Feb 28Feb 24Feb 18Feb 10Feb 3

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 3Oct 7Oct 11Oct 13Oct 16Oct 18Oct 20Oct 23Oct 27
32°FOct 13Oct 17Oct 20Oct 22Oct 25Oct 28Oct 30Nov 1Nov 6
28°FOct 23Oct 28Nov 1Nov 2Nov 4Nov 7Nov 10Nov 14Nov 20
24°FNov 1Nov 5Nov 8Nov 11Nov 14Nov 18Nov 22Nov 27Dec 3
20°FNov 9Nov 14Nov 18Nov 23Nov 28Dec 1Dec 5Dec 10Dec 21
16°FNov 17Nov 26Dec 1Dec 6Dec 11Dec 17Dec 23Dec 29Jan 6

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°F188182176171167162158153146
32°F210204198193189185179173165
28°F234226221217213209205199190
24°F263253246242237233227222214
20°F293282274267262256250243236
16°F320308301294288282276267257

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
4,730
Cooling degree days, base 65°F
1,057
Growing degree days, base 40°F
6,243
Growing degree days, base 45°F
4,907
Growing degree days, base 50°F
3,721
Growing degree days, base 55°F
2,685
Growing degree days, base 60°F
1,795

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January995011
February812014
March648366
April32620209
May12982424
June17209642
July1311775
August3274736
September56134529
October29123234
November591164
December862018

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 12.7 km from Rowan County. Low ground, valleys and open fields freeze earlier and later than a town center or a hillside.

More

Sources

NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USC00152791 (Cave Run Lake). Public domain.