Hays County climate

Hays County Frost Dates and Growing Season

NOAA 1991-2020 normals for Dripping Springs 6 E, 18.4 km from Hays County, elevation 1084 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Dripping Springs 6 E. 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 17 and the first fall freeze around November 13, a growing season of about 242 days.

Median at 36°F
last March 31, first November 4
Median at 32°F
last March 17, first November 13
Median at 28°F
last March 4, first November 26

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 18Apr 12Apr 7Apr 4Mar 31Mar 27Mar 22Mar 17Mar 9
32°FApr 7Apr 2Mar 27Mar 21Mar 17Mar 13Mar 8Mar 3Feb 26
28°FMar 25Mar 17Mar 12Mar 7Mar 4Feb 28Feb 24Feb 15Feb 4
24°FMar 11Mar 6Feb 28Feb 24Feb 16Feb 9Jan 31Jan 25Jan 11
20°FMar 2Feb 21Feb 12Feb 4Jan 28Jan 20Jan 11Jan 3Dec 23
16°FFeb 19Feb 8Jan 31Jan 19Jan 13Jan 6Jan 3Dec 30Dec 17

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 21Oct 27Oct 30Nov 2Nov 4Nov 7Nov 11Nov 15Nov 22
32°FOct 29Nov 2Nov 6Nov 10Nov 13Nov 17Nov 22Nov 28Dec 4
28°FNov 5Nov 11Nov 16Nov 21Nov 26Dec 1Dec 4Dec 11Dec 19
24°FNov 17Nov 24Dec 1Dec 4Dec 10Dec 18Dec 27Jan 2Jan 14
20°FNov 30Dec 7Dec 14Dec 26Jan 1Jan 5Jan 13Jan 22Feb 6
16°FDec 9Dec 19Dec 30Jan 2Jan 5Jan 9Jan 17Feb 1Feb 13

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°F245235229224219214208203196
32°F269260253247242237231225216
28°F303291281274268262255249239
24°F343329318308301295287277267
20°F365365361350341334324310300
16°F365365365365365365363350332

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
100% of years
24°F or colder
97% of years
20°F or colder
76% of years
16°F or colder
35% 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
1,811
Cooling degree days, base 65°F
2,709
Growing degree days, base 40°F
10,078
Growing degree days, base 45°F
8,353
Growing degree days, base 50°F
6,729
Growing degree days, base 55°F
5,235
Growing degree days, base 60°F
3,888

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January4815114
February33015170
March18951349
April56133528
May7300758
June0467916
July05661,031
August05771,041
September3377824
October59172581
November24339283
December4439135

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 18.4 km from Hays County. 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 USC00412585 (Dripping Springs 6 E). Public domain.