Radcliff climate

Radcliff Frost Dates and Growing Season

NOAA 1991-2020 normals for Elizabethtown Wp Cs, 18.9 km from Radcliff, elevation 690 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Elizabethtown Wp Cs. 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 16 and the first fall freeze around October 25, a growing season of about 191 days.

Median at 36°F
last April 27, first October 16
Median at 32°F
last April 16, first October 25
Median at 28°F
last April 1, first November 3

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 13May 8May 4Apr 30Apr 27Apr 24Apr 21Apr 18Apr 12
32°FMay 4Apr 27Apr 22Apr 19Apr 16Apr 12Apr 9Apr 5Mar 31
28°FApr 18Apr 12Apr 8Apr 5Apr 1Mar 30Mar 27Mar 23Mar 17
24°FApr 6Apr 1Mar 29Mar 26Mar 22Mar 18Mar 14Mar 9Mar 2
20°FMar 28Mar 22Mar 17Mar 13Mar 10Mar 6Mar 2Feb 26Feb 19
16°FMar 17Mar 12Mar 7Mar 2Feb 27Feb 22Feb 18Feb 10Feb 2

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 5Oct 8Oct 11Oct 14Oct 16Oct 19Oct 21Oct 23Oct 26
32°FOct 13Oct 18Oct 21Oct 23Oct 25Oct 27Oct 29Oct 31Nov 3
28°FOct 23Oct 27Oct 30Nov 1Nov 3Nov 4Nov 7Nov 11Nov 16
24°FNov 1Nov 4Nov 7Nov 10Nov 13Nov 16Nov 19Nov 23Nov 29
20°FNov 7Nov 12Nov 16Nov 20Nov 24Nov 28Dec 1Dec 5Dec 12
16°FNov 16Nov 23Nov 28Dec 2Dec 6Dec 11Dec 17Dec 24Dec 30

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°F188182177173170166162157151
32°F210203198194191187182177168
28°F235227222218214210206200194
24°F263254247241237233228223216
20°F288279273266262257251245238
16°F313304298291285280273266257

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
4,565
Cooling degree days, base 65°F
1,136
Growing degree days, base 40°F
6,419
Growing degree days, base 45°F
5,072
Growing degree days, base 50°F
3,868
Growing degree days, base 55°F
2,810
Growing degree days, base 60°F
1,898

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January987011
February779018
March611266
April30215214
May10084452
June9237678
July1337801
August1304767
September42136545
October27320244
November596157
December865015

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 18.9 km from Radcliff. 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 USC00152512 (Elizabethtown Wp Cs). Public domain.