Covington climate

Covington Frost Dates and Growing Season

NOAA 1991-2020 normals for Covington, 1.5 km from Covington, elevation 769 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Covington. 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 March 22 and the first fall freeze around November 14, a growing season of about 238 days.

Median at 36°F
last April 3, first November 2
Median at 32°F
last March 22, first November 14
Median at 28°F
last March 6, first November 28

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°FApr 20Apr 14Apr 9Apr 5Apr 3Mar 31Mar 28Mar 24Mar 16
32°FApr 6Apr 2Mar 30Mar 26Mar 22Mar 18Mar 14Mar 7Feb 26
28°FMar 27Mar 21Mar 15Mar 11Mar 6Mar 1Feb 24Feb 17Feb 7
24°FMar 15Mar 6Feb 28Feb 21Feb 14Feb 7Feb 1Jan 27Jan 17
20°FMar 4Feb 23Feb 11Feb 2Jan 30Jan 25Jan 18Jan 10Dec 31
16°FFeb 12Feb 1Jan 30Jan 25Jan 19Jan 14Jan 8Jan 1Dec 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 22Oct 26Oct 29Nov 1Nov 2Nov 5Nov 9Nov 12Nov 19
32°FNov 1Nov 4Nov 8Nov 11Nov 14Nov 17Nov 22Nov 27Dec 2
28°FNov 9Nov 14Nov 19Nov 23Nov 28Dec 1Dec 6Dec 11Dec 22
24°FNov 20Nov 28Dec 3Dec 8Dec 14Dec 21Dec 29Jan 6Jan 16
20°FDec 2Dec 11Dec 19Dec 26Jan 1Jan 5Jan 12Jan 20Jan 31
16°FDec 11Dec 22Dec 30Jan 3Jan 7Jan 13Jan 17Jan 25Feb 3

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°F238229223219215210206202194
32°F267258250244238232227221214
28°F303290282275269262256248239
24°F337329320312305299291283268
20°F365359349342335329321311300
16°F365365365365365357347338328

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
99% of years
20°F or colder
85% of years
16°F or colder
51% 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
2,847
Cooling degree days, base 65°F
1,840
Growing degree days, base 40°F
8,261
Growing degree days, base 45°F
6,648
Growing degree days, base 50°F
5,197
Growing degree days, base 55°F
3,912
Growing degree days, base 60°F
2,792

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January682035
February511155
March35512185
April14946355
May32173607
June1360808
July0463928
August0442907
September7272715
October12463410
November3907138
December597153

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 1.5 km from Covington. 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 USC00092318 (Covington). Public domain.