Morehead City climate

Morehead City Frost Dates and Growing Season

NOAA 1991-2020 normals for Morehead City 2 Wnw, 1.5 km from Morehead City, elevation 10 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Morehead City 2 Wnw. 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 18 and the first fall freeze around November 21, a growing season of about 249 days.

Median at 36°F
last April 1, first November 9
Median at 32°F
last March 18, first November 21
Median at 28°F
last March 2, first December 5

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

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 28Nov 1Nov 4Nov 6Nov 9Nov 12Nov 16Nov 19Nov 26
32°FNov 5Nov 10Nov 14Nov 18Nov 21Nov 25Nov 30Dec 4Dec 12
28°FNov 15Nov 22Nov 26Dec 1Dec 5Dec 10Dec 18Dec 26Jan 4
24°FNov 29Dec 6Dec 14Dec 23Dec 29Jan 1Jan 6Jan 12Jan 22
20°FDec 15Dec 26Jan 1Jan 4Jan 8Jan 14Jan 18Jan 24Feb 1
16°FDec 26Jan 3Jan 7Jan 11Jan 16Jan 19Jan 23Jan 28Feb 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°F246238233228224219215210203
32°F274265259254249243238232222
28°F311301291285279273267259248
24°F343333326320312306300291280
20°F365365357349341334329322308
16°F365365365365365365355345334

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
98% of years
20°F or colder
79% of years
16°F or colder
41% 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
2,483
Cooling degree days, base 65°F
1,849
Growing degree days, base 40°F
8,583
Growing degree days, base 45°F
6,908
Growing degree days, base 50°F
5,369
Growing degree days, base 55°F
4,007
Growing degree days, base 60°F
2,836

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January599056
February486059
March3694156
April15034340
May29159595
June1348796
July0454919
August0429894
September3307754
October7799488
November28613212
December4842100

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 Morehead City. 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 USC00315830 (Morehead City 2 Wnw). Public domain.