Erath climate

Erath Frost Dates and Growing Season

NOAA 1991-2020 normals for New Iberia Acadiana Rgnl AP, 17.1 km from Erath, elevation 24 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for New Iberia Acadiana Rgnl AP. 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 February 14 and the first fall freeze around December 5, a growing season of about 298 days.

Median at 36°F
last March 3, first November 21
Median at 32°F
last February 14, first December 5
Median at 28°F
last January 28, first December 31

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°FMar 24Mar 16Mar 11Mar 7Mar 3Feb 27Feb 23Feb 17Feb 2
32°FMar 11Mar 5Feb 28Feb 22Feb 14Feb 6Jan 31Jan 23Jan 11
28°FMar 1Feb 18Feb 8Feb 1Jan 28Jan 20Jan 13Jan 2Dec 23
24°FFeb 14Feb 2Jan 30Jan 24Jan 17Jan 12Jan 7Jan 1Dec 22
20°FFeb 4Jan 31Jan 26Jan 20Jan 17Jan 12Jan 8Jan 6Jan 2
16°F–––––––––

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°FNov 4Nov 9Nov 13Nov 17Nov 21Nov 25Nov 29Dec 3Dec 11
32°FNov 14Nov 22Nov 27Dec 1Dec 5Dec 11Dec 17Dec 27Jan 7
28°FDec 1Dec 7Dec 14Dec 24Dec 31Jan 3Jan 7Jan 15Feb 1
24°FDec 15Dec 25Jan 1Jan 3Jan 6Jan 11Jan 16Jan 26Feb 5
20°FJan 1Jan 5Jan 7Jan 9Jan 12Jan 16Jan 23Jan 30Feb 2
16°F–––––––––

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°F293283275269263257251245236
32°F335323313305298289281272260
28°F365365355345337331321312300
24°F365365365365365365359347334
20°F365365365365365365365365365
16°F365365365365365365365365365

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
99% of years
28°F or colder
83% of years
24°F or colder
42% of years
20°F or colder
12% of years
16°F or colder
2% 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
1,363
Cooling degree days, base 65°F
2,934
Growing degree days, base 40°F
10,715
Growing degree days, base 45°F
8,939
Growing degree days, base 50°F
7,235
Growing degree days, base 55°F
5,653
Growing degree days, base 60°F
4,212

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January39015171
February25825223
March13765400
April36153568
May2347811
June0490940
July05551,020
August05641,029
September1437886
October30207642
November17449338
December33626208

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 17.1 km from Erath. 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 USW00053915 (New Iberia Acadiana Rgnl AP). Public domain.