Clarkrange climate

Clarkrange Frost Dates and Growing Season

NOAA 1991-2020 normals for Crossville Ed & Research, 21.4 km from Clarkrange, elevation 1810 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Crossville Ed & Research. 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 19 and the first fall freeze around October 22, a growing season of about 185 days.

Median at 36°F
last May 2, first October 12
Median at 32°F
last April 19, first October 22
Median at 28°F
last April 3, 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 19May 13May 9May 5May 2Apr 29Apr 25Apr 21Apr 15
32°FMay 7May 2Apr 28Apr 23Apr 19Apr 15Apr 9Apr 5Mar 31
28°FApr 23Apr 17Apr 10Apr 6Apr 3Mar 31Mar 28Mar 23Mar 18
24°FApr 7Apr 3Mar 30Mar 26Mar 22Mar 18Mar 14Mar 8Mar 3
20°FMar 30Mar 24Mar 19Mar 15Mar 11Mar 7Mar 2Feb 27Feb 17
16°FMar 19Mar 14Mar 8Mar 4Feb 28Feb 23Feb 17Feb 8Jan 31

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 1Oct 4Oct 7Oct 10Oct 12Oct 14Oct 17Oct 20Oct 24
32°FOct 8Oct 13Oct 16Oct 19Oct 22Oct 24Oct 26Oct 29Nov 1
28°FOct 17Oct 21Oct 25Oct 27Oct 30Nov 1Nov 4Nov 7Nov 12
24°FOct 26Oct 31Nov 2Nov 5Nov 8Nov 11Nov 14Nov 19Nov 27
20°FNov 3Nov 8Nov 12Nov 16Nov 21Nov 25Dec 1Dec 4Dec 13
16°FNov 12Nov 21Nov 27Dec 2Dec 5Dec 10Dec 16Dec 24Jan 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°F185176171167163159155149143
32°F209201195189185180175170162
28°F231223218213208204199194186
24°F257248241236231226221215208
20°F286276267261257251245237228
16°F315304296289283277269262252

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
4,825
Cooling degree days, base 65°F
731
Growing degree days, base 40°F
5,814
Growing degree days, base 45°F
4,479
Growing degree days, base 50°F
3,303
Growing degree days, base 55°F
2,288
Growing degree days, base 60°F
1,429

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January98108
February792012
March642161
April3527179
May14444375
June23144572
July2234697
August6204663
September6886470
October32810201
November620052
December868014

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 21.4 km from Clarkrange. 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 USC00402202 (Crossville Ed & Research). Public domain.