Hatch climate

Hatch Frost Dates and Growing Season

NOAA 1991-2020 normals for Caballo Dam, 29.5 km from Hatch, elevation 4239 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Caballo 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 March 25 and the first fall freeze around November 6, a growing season of about 224 days.

Median at 36°F
last April 14, first October 28
Median at 32°F
last March 25, first November 6
Median at 28°F
last March 7, first November 18

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°FMay 2Apr 27Apr 22Apr 18Apr 14Apr 9Apr 5Apr 1Mar 25
32°FApr 17Apr 8Apr 3Mar 30Mar 25Mar 20Mar 16Mar 11Mar 5
28°FMar 28Mar 19Mar 14Mar 10Mar 7Mar 3Feb 28Feb 25Feb 19
24°FMar 9Mar 3Feb 28Feb 23Feb 20Feb 16Feb 12Feb 6Jan 27
20°FFeb 25Feb 18Feb 12Feb 6Jan 31Jan 25Jan 17Jan 10Dec 28
16°FFeb 13Feb 2Jan 24Jan 14Jan 7Dec 31Dec 27Dec 21Dec 13

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 16Oct 21Oct 23Oct 26Oct 28Oct 31Nov 3Nov 6Nov 11
32°FOct 24Oct 29Nov 1Nov 4Nov 6Nov 10Nov 14Nov 17Nov 21
28°FNov 1Nov 6Nov 11Nov 14Nov 18Nov 21Nov 24Nov 27Dec 1
24°FNov 15Nov 20Nov 25Nov 28Dec 1Dec 2Dec 5Dec 9Dec 15
20°FNov 27Dec 1Dec 4Dec 8Dec 12Dec 16Dec 21Dec 26Jan 3
16°FDec 3Dec 8Dec 13Dec 17Dec 22Dec 28Jan 2Jan 11Jan 26

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°F218211205201197193187182175
32°F248240234228224219213208199
28°F277269263258253248243237226
24°F311301294288282277272266256
20°F351340333326318311303295286
16°F365365365362355347341334322

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
100% of years
20°F or colder
98% of years
16°F or colder
71% 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
2,732
Cooling degree days, base 65°F
2,115
Growing degree days, base 40°F
8,591
Growing degree days, base 45°F
6,944
Growing degree days, base 50°F
5,472
Growing degree days, base 55°F
4,186
Growing degree days, base 60°F
3,066

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January660011
February470049
March3073189
April12237368
May21202647
June0462912
July05661,031
August0499964
September5287732
October9757430
November3832126
December666015

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 29.5 km from Hatch. 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 USC00291286 (Caballo Dam). Public domain.