Zebulon climate

Zebulon Frost Dates and Growing Season

NOAA 1991-2020 normals for Clayton Wtp, 24.4 km from Zebulon, elevation 300 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Clayton Wtp. 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 3, a growing season of about 211 days.

Median at 36°F
last April 18, first October 26
Median at 32°F
last April 7, first November 3
Median at 28°F
last March 27, first November 14

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 30Apr 26Apr 23Apr 20Apr 18Apr 15Apr 12Apr 8Apr 3
32°FApr 20Apr 16Apr 13Apr 10Apr 7Apr 4Apr 1Mar 29Mar 23
28°FApr 12Apr 7Apr 3Mar 31Mar 27Mar 23Mar 19Mar 15Mar 7
24°FApr 2Mar 26Mar 20Mar 15Mar 11Mar 8Mar 4Feb 28Feb 23
20°FMar 19Mar 11Mar 6Mar 2Feb 27Feb 22Feb 16Feb 9Jan 31
16°FMar 5Feb 27Feb 19Feb 13Feb 7Feb 2Jan 28Jan 18Jan 8

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

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°F209203199194191187183179173
32°F233225219215211207203198191
28°F258249243237233229224219211
24°F290279272265260254248242233
20°F325311304297292286278269260
16°F361346334329321314308301293

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
92% 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
3,394
Cooling degree days, base 65°F
1,579
Growing degree days, base 40°F
7,576
Growing degree days, base 45°F
6,053
Growing degree days, base 50°F
4,692
Growing degree days, base 55°F
3,491
Growing degree days, base 60°F
2,453

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January752031
February611136
March4656123
April20937297
May55139549
June3307754
July0434899
August0388852
September15219654
October18044339
November4414113
December663145

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 24.4 km from Zebulon. 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 USC00311820 (Clayton Wtp). Public domain.