Nederland climate

Nederland Frost Dates and Growing Season

NOAA 1991-2020 normals for Port Arthur Se Tx AP, 3.8 km from Nederland, elevation 16 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Port Arthur Se Tx 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 7, a growing season of about 301 days.

Median at 36°F
last March 4, first November 23
Median at 32°F
last February 14, first December 7
Median at 28°F
last January 28, first January 1

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 27Mar 18Mar 13Mar 8Mar 4Feb 28Feb 23Feb 17Feb 5
32°FMar 13Mar 4Feb 27Feb 21Feb 14Feb 7Feb 1Jan 27Jan 17
28°FMar 3Feb 20Feb 10Feb 2Jan 28Jan 22Jan 14Jan 7Dec 23
24°FFeb 24Feb 7Feb 1Jan 24Jan 16Jan 10Jan 5Dec 31Dec 21
20°F–––––––––
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 3Nov 10Nov 15Nov 19Nov 23Nov 27Dec 1Dec 4Dec 12
32°FNov 15Nov 23Nov 29Dec 2Dec 7Dec 13Dec 22Jan 1Jan 9
28°FDec 1Dec 8Dec 16Dec 27Jan 1Jan 5Jan 10Jan 19Feb 3
24°FDec 12Dec 27Jan 1Jan 4Jan 7Jan 11Jan 18Jan 29Feb 11
20°F–––––––––
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°F298286278271264258251243235
32°F338327317308301293286276263
28°F365365353345338331324312300
24°F365365365365365365359349334
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
79% of years
24°F or colder
38% of years
20°F or colder
7% of years
16°F or colder
1% 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
1,262
Cooling degree days, base 65°F
3,076
Growing degree days, base 40°F
10,952
Growing degree days, base 45°F
9,165
Growing degree days, base 50°F
7,445
Growing degree days, base 55°F
5,839
Growing degree days, base 60°F
4,377

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January36715178
February23526239
March12572419
April33162579
May2358822
June0510960
July05771,042
August05811,046
September0452901
October26231670
November15865368
December31727222

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 3.8 km from Nederland. 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 USW00012917 (Port Arthur Se Tx AP). Public domain.