Fairgrove climate

Fairgrove Frost Dates and Growing Season

NOAA 1991-2020 normals for Caro Wwtp, 13 km from Fairgrove, elevation 690 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Caro Wwtp. 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 May 7 and the first fall freeze around October 9, a growing season of about 154 days.

Median at 36°F
last May 20, first October 1
Median at 32°F
last May 7, first October 9
Median at 28°F
last April 27, first October 23

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°FJun 4May 31May 27May 23May 20May 17May 14May 9May 4
32°FMay 24May 19May 15May 11May 7May 4Apr 30Apr 28Apr 24
28°FMay 15May 7May 2Apr 30Apr 27Apr 24Apr 21Apr 17Apr 12
24°FApr 29Apr 24Apr 20Apr 17Apr 14Apr 12Apr 8Apr 4Mar 31
20°FApr 19Apr 15Apr 10Apr 6Apr 4Apr 1Mar 29Mar 24Mar 18
16°FApr 10Apr 4Mar 31Mar 29Mar 25Mar 21Mar 18Mar 14Mar 9

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°FSep 15Sep 21Sep 24Sep 27Oct 1Oct 2Oct 5Oct 8Oct 13
32°FSep 25Oct 1Oct 3Oct 6Oct 9Oct 13Oct 16Oct 21Oct 26
28°FOct 4Oct 10Oct 15Oct 19Oct 23Oct 28Nov 1Nov 3Nov 7
24°FOct 19Oct 27Oct 31Nov 2Nov 5Nov 8Nov 11Nov 16Nov 21
20°FNov 2Nov 7Nov 11Nov 15Nov 18Nov 21Nov 24Nov 29Dec 4
16°FNov 14Nov 19Nov 23Nov 26Nov 29Dec 2Dec 6Dec 11Dec 17

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°F154146141138132128123118111
32°F175168163158154150145140133
28°F199193187183179173168162154
24°F226217212206202199196190181
20°F252243237232228224219214207
16°F273264259254249244239234227

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
7,120
Cooling degree days, base 65°F
536
Growing degree days, base 40°F
4,448
Growing degree days, base 45°F
3,401
Growing degree days, base 50°F
2,488
Growing degree days, base 55°F
1,702
Growing degree days, base 60°F
1,042

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,33300
February1,17200
March1,011111
April621354
May29831236
June70111491
July16194643
August28141578
September15752353
October4795107
November801015
December1,13601

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 13 km from Fairgrove. 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 USC00201299 (Caro Wwtp). Public domain.