George West climate

George West Frost Dates and Growing Season

NOAA 1991-2020 normals for Choke Canyon Dam, 20 km from George West, elevation 230 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Choke Canyon Dam. 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 8 and the first fall freeze around December 6, a growing season of about 302 days.

Median at 36°F
last February 28, first November 24
Median at 32°F
last February 8, first December 6
Median at 28°F
last January 23, first December 25

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 13Mar 8Mar 3Feb 28Feb 24Feb 18Feb 12Feb 2
32°FMar 8Mar 1Feb 22Feb 15Feb 8Feb 1Jan 27Jan 19Jan 1
28°FFeb 28Feb 13Feb 4Jan 31Jan 23Jan 15Jan 6Dec 29Dec 16
24°FFeb 15Feb 4Jan 27Jan 19Jan 10Jan 5Jan 1Dec 23Dec 13
20°FFeb 6Jan 20Jan 9Jan 7Jan 5Jan 2Dec 30Dec 19Dec 16
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 5Nov 12Nov 17Nov 20Nov 24Nov 29Dec 2Dec 7Dec 14
32°FNov 17Nov 22Nov 29Dec 2Dec 6Dec 11Dec 18Dec 28Jan 6
28°FNov 28Dec 4Dec 10Dec 18Dec 25Jan 1Jan 6Jan 17Feb 1
24°FDec 6Dec 14Dec 21Dec 29Jan 2Jan 6Jan 14Jan 30Feb 9
20°FDec 15Dec 18Dec 27Jan 1Jan 4Jan 6Jan 8Jan 18Feb 1
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°F302291283276270265259252241
32°F341328318309302295288279268
28°F365365354346337329322309295
24°F365365365365365365357346327
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
78% of years
24°F or colder
40% of years
20°F or colder
10% of years
16°F or colder
0% 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
1,275
Cooling degree days, base 65°F
3,317
Growing degree days, base 40°F
11,188
Growing degree days, base 45°F
9,410
Growing degree days, base 50°F
7,702
Growing degree days, base 55°F
6,100
Growing degree days, base 60°F
4,629

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January37316177
February23831247
March11892449
April29188610
May2391854
June0537987
July06061,071
August06311,096
September1461911
October25261701
November15381393
December33623207

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 20 km from George West. 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 USC00411720 (Choke Canyon Dam). Public domain.