Seaford climate

Seaford Frost Dates and Growing Season

NOAA 1991-2020 normals for Wantagh Cedar Creek, 1.9 km from Seaford, elevation 10 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Wantagh Cedar Creek. 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 3 and the first fall freeze around November 11, a growing season of about 221 days.

Median at 36°F
last April 16, first October 30
Median at 32°F
last April 3, first November 11
Median at 28°F
last March 22, first November 23

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 22Apr 18Apr 16Apr 14Apr 11Apr 8Apr 4
32°FApr 18Apr 13Apr 9Apr 5Apr 3Apr 1Mar 30Mar 26Mar 19
28°FApr 5Apr 1Mar 29Mar 26Mar 22Mar 18Mar 15Mar 11Mar 5
24°FMar 26Mar 21Mar 16Mar 13Mar 10Mar 6Mar 2Feb 26Feb 21
20°FMar 17Mar 11Mar 7Mar 2Feb 27Feb 22Feb 16Feb 9Feb 3
16°FMar 5Feb 27Feb 21Feb 14Feb 9Feb 4Jan 31Jan 25Jan 15

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 17Oct 22Oct 25Oct 28Oct 30Nov 2Nov 4Nov 7Nov 12
32°FOct 31Nov 2Nov 5Nov 8Nov 11Nov 15Nov 18Nov 23Nov 30
28°FNov 8Nov 13Nov 17Nov 20Nov 23Nov 28Dec 2Dec 5Dec 11
24°FNov 17Nov 22Nov 28Dec 2Dec 5Dec 10Dec 15Dec 21Dec 28
20°FDec 1Dec 8Dec 15Dec 20Dec 24Dec 30Jan 3Jan 8Jan 17
16°FDec 16Dec 25Dec 30Jan 3Jan 7Jan 12Jan 16Jan 22Feb 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°F214208203200196192188184177
32°F244235229224221217213208202
28°F270263256251246241235231224
24°F299290284279274269263256248
20°F327318311305300295290283273
16°F357340334330324319312306299

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
93% 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
4,591
Cooling degree days, base 65°F
1,115
Growing degree days, base 40°F
6,187
Growing degree days, base 45°F
4,828
Growing degree days, base 50°F
3,651
Growing degree days, base 55°F
2,644
Growing degree days, base 60°F
1,806

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January94103
February80603
March704016
April4143100
May15438350
June18198630
July1369834
August1331795
September29154574
October23022270
November516065
December778013

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 1.9 km from Seaford. 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 USC00308946 (Wantagh Cedar Creek). Public domain.