Grenada County climate

Grenada County Frost Dates and Growing Season

NOAA 1991-2020 normals for Grenada, 1.5 km from Grenada County, elevation 237 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Grenada. 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 4, a growing season of about 222 days.

Median at 36°F
last April 9, first October 26
Median at 32°F
last March 28, first November 4
Median at 28°F
last March 12, first November 15

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 27Apr 22Apr 16Apr 12Apr 9Apr 6Apr 3Mar 30Mar 23
32°FApr 14Apr 8Apr 4Apr 1Mar 28Mar 23Mar 19Mar 14Mar 8
28°FApr 1Mar 25Mar 20Mar 16Mar 12Mar 8Mar 3Feb 28Feb 22
24°FMar 18Mar 11Mar 6Mar 2Feb 27Feb 23Feb 17Feb 11Feb 1
20°FMar 8Mar 2Feb 26Feb 19Feb 12Feb 6Jan 31Jan 25Jan 14
16°FFeb 28Feb 19Feb 9Feb 2Jan 30Jan 23Jan 16Jan 10Dec 31

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 13Oct 18Oct 21Oct 24Oct 26Oct 29Nov 1Nov 4Nov 8
32°FOct 21Oct 27Oct 30Nov 1Nov 4Nov 6Nov 9Nov 14Nov 21
28°FNov 1Nov 5Nov 8Nov 11Nov 15Nov 20Nov 24Dec 1Dec 6
24°FNov 8Nov 14Nov 19Nov 25Nov 30Dec 4Dec 10Dec 19Jan 1
20°FNov 19Nov 29Dec 5Dec 14Dec 22Dec 29Jan 2Jan 9Jan 20
16°FDec 6Dec 21Dec 28Jan 1Jan 5Jan 10Jan 15Jan 22Feb 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°F222214208204199195190184177
32°F246238232227222217212205198
28°F274265258253248242236230221
24°F308299290283277270263257249
20°F342333324315308301293283270
16°F365365352342335330323311302

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
97% of years
16°F or colder
80% 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
2,898
Cooling degree days, base 65°F
2,034
Growing degree days, base 40°F
8,474
Growing degree days, base 45°F
6,890
Growing degree days, base 50°F
5,453
Growing degree days, base 55°F
4,160
Growing degree days, base 60°F
3,017

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January698247
February532368
March34717204
April15064376
May32196629
June0389838
July0493958
August0468933
September8302744
October13486426
November38712161
December611369

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 Grenada County. 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 USC00223645 (Grenada). Public domain.