Waverly climate

Waverly Frost Dates and Growing Season

NOAA 1991-2020 normals for Waverly AP, 5.8 km from Waverly, elevation 749 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Waverly AP. 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 2 and the first fall freeze around November 4, a growing season of about 218 days.

Median at 36°F
last April 15, first October 26
Median at 32°F
last April 2, first November 4
Median at 28°F
last March 18, first November 13

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 4Apr 28Apr 23Apr 20Apr 15Apr 12Apr 8Apr 4Mar 30
32°FApr 21Apr 14Apr 8Apr 5Apr 2Mar 30Mar 25Mar 20Mar 13
28°FApr 7Apr 1Mar 28Mar 23Mar 18Mar 15Mar 10Mar 5Feb 27
24°FMar 27Mar 19Mar 14Mar 9Mar 5Mar 2Feb 26Feb 21Feb 13
20°FMar 15Mar 7Mar 2Feb 27Feb 23Feb 18Feb 13Feb 7Feb 1
16°FMar 3Feb 25Feb 18Feb 12Feb 8Feb 4Jan 31Jan 27Jan 19

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 12Oct 17Oct 21Oct 24Oct 26Oct 29Nov 1Nov 3Nov 7
32°FOct 22Oct 27Oct 31Nov 2Nov 4Nov 6Nov 10Nov 13Nov 20
28°FNov 1Nov 5Nov 8Nov 11Nov 13Nov 17Nov 21Nov 26Dec 1
24°FNov 8Nov 12Nov 17Nov 21Nov 25Nov 30Dec 3Dec 7Dec 14
20°FNov 17Nov 24Nov 29Dec 3Dec 7Dec 12Dec 18Dec 24Jan 1
16°FNov 29Dec 5Dec 12Dec 19Dec 25Dec 29Jan 3Jan 8Jan 16

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°F216208202197193188183179171
32°F240232227222218212207201192
28°F265257251245240235229223215
24°F291281275269263258252246238
20°F318307299294288282276269258
16°F338331325318312306301294282

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
3,729
Cooling degree days, base 65°F
1,544
Growing degree days, base 40°F
7,407
Growing degree days, base 45°F
5,944
Growing degree days, base 50°F
4,628
Growing degree days, base 55°F
3,455
Growing degree days, base 60°F
2,423

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January883017
February664035
March46410139
April21148314
May64134536
June3288735
July0405869
August1392857
September23207634
October18557352
November4774109
December755031

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 5.8 km from Waverly. 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 USC00409493 (Waverly AP). Public domain.