Caldwell County climate

Caldwell County Frost Dates and Growing Season

NOAA 1991-2020 normals for Luling, 18.3 km from Caldwell County, elevation 400 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Luling. 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 5 and the first fall freeze around November 23, a growing season of about 263 days.

Median at 36°F
last March 22, first November 10
Median at 32°F
last March 5, first November 23
Median at 28°F
last February 17, first December 6

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 14Apr 6Apr 1Mar 27Mar 22Mar 16Mar 11Mar 5Feb 26
32°FApr 3Mar 23Mar 14Mar 9Mar 5Mar 1Feb 26Feb 18Feb 7
28°FMar 13Mar 6Mar 1Feb 23Feb 17Feb 9Feb 1Jan 25Jan 11
24°FMar 3Feb 21Feb 12Feb 4Jan 28Jan 19Jan 9Dec 31Dec 22
20°FFeb 24Feb 7Jan 29Jan 18Jan 11Jan 5Dec 31Dec 25Dec 14
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°FOct 27Nov 1Nov 4Nov 7Nov 10Nov 14Nov 18Nov 23Dec 1
32°FNov 3Nov 9Nov 14Nov 19Nov 23Nov 28Dec 1Dec 6Dec 14
28°FNov 13Nov 21Nov 27Dec 1Dec 6Dec 11Dec 18Dec 28Jan 7
24°FNov 24Dec 3Dec 11Dec 19Dec 26Jan 1Jan 7Jan 15Feb 2
20°FDec 5Dec 14Dec 24Dec 30Jan 2Jan 7Jan 13Jan 22Feb 10
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°F266257249243237232225218209
32°F294285276269263256250242232
28°F337322313305297289280270258
24°F365364354346335328317306291
20°F365365365365365365358347330
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
100% of years
28°F or colder
98% of years
24°F or colder
81% of years
20°F or colder
39% of years
16°F or colder
9% 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
1,547
Cooling degree days, base 65°F
3,192
Growing degree days, base 40°F
10,801
Growing degree days, base 45°F
9,043
Growing degree days, base 50°F
7,375
Growing degree days, base 55°F
5,830
Growing degree days, base 60°F
4,432

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January42111144
February29322198
March15873395
April45158564
May5363823
June0535985
July06291,094
August06431,108
September1449899
October43226649
November19564343
December38718173

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 18.3 km from Caldwell 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 USC00415429 (Luling). Public domain.