Sheldon climate

Sheldon Frost Dates and Growing Season

NOAA 1991-2020 normals for Baytown, 14.2 km from Sheldon, elevation 26 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Baytown. 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 20 and the first fall freeze around December 4, a growing season of about 292 days.

Median at 36°F
last March 6, first November 20
Median at 32°F
last February 20, first December 4
Median at 28°F
last January 30, first December 28

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 28Mar 19Mar 14Mar 10Mar 6Mar 2Feb 26Feb 20Feb 13
32°FMar 14Mar 6Mar 2Feb 25Feb 20Feb 12Feb 6Jan 31Jan 23
28°FMar 1Feb 20Feb 10Feb 3Jan 30Jan 25Jan 18Jan 10Dec 25
24°FFeb 11Feb 2Jan 29Jan 22Jan 16Jan 12Jan 6Dec 31Dec 18
20°FFeb 3Feb 1Jan 23Jan 16Jan 13Jan 10Jan 7Jan 2Dec 28
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 2Nov 7Nov 12Nov 16Nov 20Nov 24Nov 29Dec 3Dec 10
32°FNov 12Nov 19Nov 25Dec 1Dec 4Dec 9Dec 16Dec 25Jan 4
28°FNov 25Dec 4Dec 10Dec 18Dec 28Jan 1Jan 6Jan 15Jan 29
24°FDec 9Dec 19Dec 28Jan 1Jan 4Jan 9Jan 14Jan 23Feb 2
20°FDec 25Jan 1Jan 3Jan 7Jan 10Jan 13Jan 19Feb 1Feb 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°F291280272266259253247240231
32°F329314306298292283275268257
28°F365352344336331322311302288
24°F365365365365365357347339328
20°F365365365365365365365365358
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
87% of years
24°F or colder
44% of years
20°F or colder
12% 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
1,436
Cooling degree days, base 65°F
2,828
Growing degree days, base 40°F
10,541
Growing degree days, base 45°F
8,772
Growing degree days, base 50°F
7,082
Growing degree days, base 55°F
5,509
Growing degree days, base 60°F
4,082

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January4089150
February27115201
March14554384
April42132541
May2326789
June0478928
July05601,025
August05671,032
September1413862
October31204640
November18053343
December35617188

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 14.2 km from Sheldon. 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 USC00410586 (Baytown). Public domain.