Coventry climate

Coventry Frost Dates and Growing Season

NOAA 1991-2020 normals for Coventry 2, 11 km from Coventry, elevation 280 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Coventry 2. 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 22 and the first fall freeze around October 20, a growing season of about 179 days.

Median at 36°F
last May 3, first October 9
Median at 32°F
last April 22, first October 20
Median at 28°F
last April 10, first November 1

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

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°F175168164160157154150146141
32°F198192188183179176172167160
28°F221215210207204200196192186
24°F246240235230226222218214208
20°F271263257253249245241236230
16°F290282277273269264259254247

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
5,987
Cooling degree days, base 65°F
750
Growing degree days, base 40°F
5,088
Growing degree days, base 45°F
3,942
Growing degree days, base 50°F
2,940
Growing degree days, base 55°F
2,071
Growing degree days, base 60°F
1,343

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,16500
February99700
March88901
April502479
May20727292
June37134547
July2290753
August5220680
September9871424
October4005139
November696024
December99001

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 11 km from Coventry. 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 USC00371875 (Coventry 2). Public domain.