Deltaville climate

Deltaville Frost Dates and Growing Season

NOAA 1991-2020 normals for N, 16.3 km from Deltaville, elevation 4 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for N. 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 1 and the first fall freeze around November 10, a growing season of about 223 days.

Median at 36°F
last April 15, first November 1
Median at 32°F
last April 1, first November 10
Median at 28°F
last March 21, 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°FMay 3Apr 25Apr 21Apr 18Apr 15Apr 12Apr 8Apr 4Mar 31
32°FApr 15Apr 10Apr 7Apr 4Apr 1Mar 31Mar 28Mar 25Mar 20
28°FApr 3Mar 31Mar 28Mar 25Mar 21Mar 18Mar 15Mar 10Mar 5
24°FMar 25Mar 19Mar 14Mar 11Mar 7Mar 4Feb 28Feb 25Feb 17
20°FMar 14Mar 8Mar 3Feb 28Feb 24Feb 18Feb 11Feb 5Jan 28
16°FMar 2Feb 23Feb 16Feb 9Feb 4Jan 31Jan 24Jan 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 18Oct 23Oct 26Oct 29Nov 1Nov 2Nov 5Nov 8Nov 12
32°FOct 31Nov 2Nov 5Nov 8Nov 10Nov 13Nov 16Nov 20Nov 26
28°FNov 7Nov 11Nov 15Nov 19Nov 23Nov 27Dec 1Dec 4Dec 10
24°FNov 18Nov 25Nov 30Dec 3Dec 6Dec 11Dec 17Dec 23Dec 31
20°FDec 3Dec 9Dec 16Dec 21Dec 25Dec 29Jan 2Jan 8Jan 17
16°FDec 16Dec 24Dec 29Jan 1Jan 6Jan 11Jan 16Jan 23Feb 2

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°F217211207202199195190185177
32°F242236231227223219216212205
28°F268262256251247242238233226
24°F300292285279274270265259251
20°F333323315307303298291285276
16°F365355344335330322315307301

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
90% 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
3,944
Cooling degree days, base 65°F
1,287
Growing degree days, base 40°F
6,860
Growing degree days, base 45°F
5,420
Growing degree days, base 50°F
4,148
Growing degree days, base 55°F
3,033
Growing degree days, base 60°F
2,083

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January832018
February710023
March596269
April30022208
May9786455
June9244686
July0384849
August0333798
September16179613
October19834310
November470290
December718028

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 16.3 km from Deltaville. 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 USC00446161 (N). Public domain.