Amite County climate

Amite County Frost Dates and Growing Season

NOAA 1991-2020 normals for Liberty, 1.6 km from Amite County, elevation 328 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Liberty. 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 25 and the first fall freeze around November 8, a growing season of about 230 days.

Median at 36°F
last April 8, first November 1
Median at 32°F
last March 25, first November 8
Median at 28°F
last March 6, first November 20

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 24Apr 19Apr 14Apr 10Apr 8Apr 5Apr 1Mar 27Mar 19
32°FApr 15Apr 8Apr 4Mar 31Mar 25Mar 18Mar 14Mar 5Feb 26
28°FApr 1Mar 23Mar 16Mar 11Mar 6Mar 2Feb 26Feb 20Feb 9
24°FMar 13Mar 6Mar 1Feb 26Feb 21Feb 14Feb 7Jan 31Jan 17
20°FMar 3Feb 26Feb 19Feb 12Feb 4Jan 31Jan 23Jan 11Dec 27
16°FFeb 25Feb 18Feb 10Feb 1Jan 28Jan 20Jan 12Jan 4Dec 24

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 22Oct 26Oct 30Nov 1Nov 4Nov 6Nov 9Nov 15
32°FOct 25Oct 31Nov 3Nov 6Nov 8Nov 11Nov 15Nov 19Nov 25
28°FNov 5Nov 8Nov 12Nov 16Nov 20Nov 24Nov 28Dec 2Dec 12
24°FNov 12Nov 19Nov 26Dec 1Dec 4Dec 8Dec 17Dec 30Jan 9
20°FNov 25Dec 2Dec 8Dec 16Dec 26Jan 1Jan 8Jan 18Feb 1
16°FDec 9Dec 19Dec 28Jan 1Jan 8Jan 14Jan 22Feb 1Feb 6

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°F231222216212207203199194188
32°F260250242236230224218212203
28°F296281271266259253246238228
24°F330315306300291284276266256
20°F365351340334325316307300285
16°F365365365365357346335323308

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
99% of years
20°F or colder
87% of years
16°F or colder
58% 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
2,108
Cooling degree days, base 65°F
2,216
Growing degree days, base 40°F
9,310
Growing degree days, base 45°F
7,603
Growing degree days, base 50°F
6,010
Growing degree days, base 55°F
4,577
Growing degree days, base 60°F
3,302

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January5235103
February4006114
March23530286
April11273414
May14241693
June0412862
July0476941
August0480945
September4337783
October74129522
November28619226
December4617122

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 1.6 km from Amite 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 USC00225070 (Liberty). Public domain.