DeSoto County climate

DeSoto County Frost Dates and Growing Season

NOAA 1991-2020 normals for Hernando, 8.1 km from DeSoto County, elevation 380 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Hernando. 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 28 and the first fall freeze around November 5, a growing season of about 223 days.

Median at 36°F
last April 6, first October 29
Median at 32°F
last March 28, first November 5
Median at 28°F
last March 13, first November 16

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 22Apr 17Apr 13Apr 10Apr 6Apr 4Apr 1Mar 28Mar 20
32°FApr 12Apr 6Apr 2Mar 31Mar 28Mar 23Mar 19Mar 14Mar 6
28°FApr 1Mar 26Mar 21Mar 17Mar 13Mar 10Mar 5Mar 1Feb 24
24°FMar 20Mar 14Mar 10Mar 6Mar 3Feb 28Feb 24Feb 18Feb 10
20°FMar 11Mar 5Mar 1Feb 24Feb 19Feb 13Feb 6Jan 29Jan 18
16°FMar 2Feb 23Feb 14Feb 7Jan 31Jan 27Jan 21Jan 13Jan 4

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 16Oct 21Oct 23Oct 26Oct 29Oct 31Nov 1Nov 5Nov 9
32°FOct 25Oct 30Nov 1Nov 3Nov 5Nov 8Nov 11Nov 15Nov 20
28°FNov 2Nov 6Nov 10Nov 13Nov 16Nov 19Nov 23Nov 29Dec 5
24°FNov 9Nov 15Nov 20Nov 23Nov 28Dec 2Dec 6Dec 14Dec 23
20°FNov 17Nov 27Dec 2Dec 8Dec 14Dec 22Dec 27Jan 2Jan 13
16°FDec 1Dec 14Dec 22Dec 29Jan 1Jan 6Jan 11Jan 18Jan 31

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°F224217212208204201196191185
32°F246238232227223219215209202
28°F271262256251246242237230223
24°F298289282275270264258252243
20°F333321312306300293287280270
16°F365352344336330322314306296

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
99% of years
16°F or colder
88% 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
3,288
Cooling degree days, base 65°F
1,922
Growing degree days, base 40°F
8,079
Growing degree days, base 45°F
6,555
Growing degree days, base 50°F
5,175
Growing degree days, base 55°F
3,938
Growing degree days, base 60°F
2,855

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January777130
February597149
March41512161
April16755353
May34187619
June1371820
July0478942
August0459924
September14276712
October16174391
November4367129
December686145

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 8.1 km from DeSoto County. 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 USC00223975 (Hernando). Public domain.