Henderson climate

Henderson Frost Dates and Growing Season

NOAA 1991-2020 normals for Aurora, 17.8 km from Henderson, elevation 1785 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Aurora. 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 April 21 and the first fall freeze around October 15, a growing season of about 176 days.

Median at 36°F
last May 1, first October 7
Median at 32°F
last April 21, first October 15
Median at 28°F
last April 11, first October 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°FMay 14May 9May 5May 3May 1Apr 29Apr 27Apr 23Apr 18
32°FMay 4Apr 30Apr 28Apr 25Apr 21Apr 19Apr 16Apr 12Apr 8
28°FApr 25Apr 21Apr 18Apr 15Apr 11Apr 8Apr 5Apr 2Mar 27
24°FApr 18Apr 12Apr 8Apr 4Apr 1Mar 30Mar 26Mar 21Mar 15
20°FApr 8Apr 3Mar 31Mar 28Mar 23Mar 19Mar 15Mar 11Mar 6
16°FMar 31Mar 26Mar 21Mar 17Mar 13Mar 10Mar 6Mar 3Feb 27

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°FSep 24Sep 29Oct 2Oct 4Oct 7Oct 9Oct 12Oct 14Oct 18
32°FOct 1Oct 5Oct 9Oct 13Oct 15Oct 17Oct 21Oct 24Oct 28
28°FOct 10Oct 16Oct 19Oct 23Oct 26Oct 29Nov 1Nov 3Nov 7
24°FOct 19Oct 25Oct 29Nov 1Nov 4Nov 6Nov 9Nov 12Nov 19
20°FOct 29Nov 2Nov 5Nov 8Nov 11Nov 15Nov 18Nov 22Nov 27
16°FNov 3Nov 9Nov 13Nov 17Nov 21Nov 25Nov 28Dec 1Dec 8

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°F174168164161158154150146140
32°F194188183179176172168163156
28°F217209204199195191187183176
24°F236229224219215211206200193
20°F257248242237232227222215207
16°F273266261255251246240233225

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
100% of years
16°F or colder
100% 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
6,010
Cooling degree days, base 65°F
1,037
Growing degree days, base 40°F
5,656
Growing degree days, base 45°F
4,474
Growing degree days, base 50°F
3,417
Growing degree days, base 55°F
2,495
Growing degree days, base 60°F
1,700

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,23500
February1,00802
March772034
April4438128
May16564375
June18237669
July1333797
August6274733
September92109471
October38112175
November761032
December1,12801

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 17.8 km from Henderson. 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 USC00250445 (Aurora). Public domain.