Chesapeake climate

Chesapeake Frost Dates and Growing Season

NOAA 1991-2020 normals for Huntington Swg Pl, 6.8 km from Chesapeake, elevation 520 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Huntington Swg Pl. 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 12 and the first fall freeze around October 30, a growing season of about 200 days.

Median at 36°F
last April 26, first October 20
Median at 32°F
last April 12, first October 30
Median at 28°F
last March 31, first November 8

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 13May 8May 3Apr 30Apr 26Apr 22Apr 19Apr 17Apr 12
32°FMay 2Apr 23Apr 19Apr 16Apr 12Apr 8Apr 5Apr 2Mar 30
28°FApr 13Apr 8Apr 4Apr 1Mar 31Mar 28Mar 24Mar 20Mar 13
24°FApr 1Mar 28Mar 24Mar 21Mar 17Mar 14Mar 10Mar 4Feb 26
20°FMar 22Mar 17Mar 13Mar 9Mar 5Mar 1Feb 26Feb 20Feb 10
16°FMar 16Mar 8Mar 2Feb 27Feb 21Feb 14Feb 8Feb 3Jan 28

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 7Oct 12Oct 15Oct 17Oct 20Oct 22Oct 25Oct 28Oct 31
32°FOct 16Oct 21Oct 24Oct 27Oct 30Nov 1Nov 2Nov 6Nov 10
28°FOct 29Nov 1Nov 3Nov 5Nov 8Nov 10Nov 13Nov 17Nov 24
24°FNov 5Nov 9Nov 13Nov 16Nov 20Nov 23Nov 28Dec 2Dec 8
20°FNov 14Nov 20Nov 26Dec 1Dec 4Dec 9Dec 13Dec 19Dec 27
16°FNov 29Dec 6Dec 12Dec 16Dec 22Dec 27Dec 31Jan 5Jan 13

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°F195190185181176172167162154
32°F219212208204200195190184177
28°F243237232227223219216211204
24°F276266260254248243239233227
20°F305295288281275270264257248
16°F331322314307301296289282271

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
4,419
Cooling degree days, base 65°F
1,260
Growing degree days, base 40°F
6,610
Growing degree days, base 45°F
5,240
Growing degree days, base 50°F
4,023
Growing degree days, base 55°F
2,953
Growing degree days, base 60°F
2,034

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January955010
February769012
March622266
April29021228
May100100467
June10256696
July0366831
August1331795
September37158572
October25425261
November560169
December822017

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 6.8 km from Chesapeake. 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 USC00464397 (Huntington Swg Pl). Public domain.