Wilmore climate

Wilmore Frost Dates and Growing Season

NOAA 1991-2020 normals for Dix Dam, 9.4 km from Wilmore, elevation 870 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Dix Dam. 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 7 and the first fall freeze around November 1, a growing season of about 206 days.

Median at 36°F
last April 21, first October 22
Median at 32°F
last April 7, first November 1
Median at 28°F
last March 29, 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 10May 2Apr 27Apr 23Apr 21Apr 18Apr 15Apr 11Apr 5
32°FApr 24Apr 19Apr 15Apr 11Apr 7Apr 5Apr 2Mar 31Mar 25
28°FApr 11Apr 5Apr 3Mar 31Mar 29Mar 25Mar 21Mar 17Mar 11
24°FApr 2Mar 28Mar 24Mar 20Mar 16Mar 12Mar 8Mar 4Feb 26
20°FMar 26Mar 19Mar 14Mar 9Mar 5Mar 1Feb 25Feb 19Feb 11
16°FMar 18Mar 9Mar 3Feb 26Feb 20Feb 14Feb 9Feb 3Jan 26

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 14Oct 18Oct 20Oct 22Oct 24Oct 27Oct 30Nov 2
32°FOct 20Oct 23Oct 26Oct 29Nov 1Nov 2Nov 4Nov 7Nov 11
28°FOct 30Nov 1Nov 3Nov 5Nov 8Nov 11Nov 13Nov 16Nov 19
24°FNov 4Nov 8Nov 11Nov 14Nov 17Nov 19Nov 23Nov 27Dec 3
20°FNov 11Nov 16Nov 20Nov 24Nov 28Dec 1Dec 6Dec 11Dec 18
16°FNov 21Nov 27Dec 2Dec 7Dec 11Dec 17Dec 22Dec 29Jan 7

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°F204197192187183179175169163
32°F224217213209206202197192184
28°F244239234230226222218212207
24°F269261254248244240235231224
20°F298286278273267261255248240
16°F324314306300293285279273261

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
4,180
Cooling degree days, base 65°F
1,288
Growing degree days, base 40°F
6,837
Growing degree days, base 45°F
5,445
Growing degree days, base 50°F
4,197
Growing degree days, base 55°F
3,084
Growing degree days, base 60°F
2,110

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January902015
February720020
March547393
April24425267
May75110501
June5269714
July0366831
August1324787
September32155573
October21035312
November585270
December859014

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 9.4 km from Wilmore. 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 USC00152214 (Dix Dam). Public domain.