Horton climate

Horton Frost Dates and Growing Season

NOAA 1991-2020 normals for Horton, 0.9 km from Horton, elevation 1032 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Horton. 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 18 and the first fall freeze around October 17, a growing season of about 180 days.

Median at 36°F
last April 29, first October 7
Median at 32°F
last April 18, first October 17
Median at 28°F
last April 9, first October 27

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 11May 6May 4May 1Apr 29Apr 26Apr 23Apr 19Apr 14
32°FMay 2Apr 27Apr 24Apr 21Apr 18Apr 15Apr 12Apr 9Apr 3
28°FApr 23Apr 19Apr 15Apr 12Apr 9Apr 6Apr 3Mar 31Mar 24
24°FApr 16Apr 9Apr 6Apr 3Mar 31Mar 28Mar 24Mar 20Mar 13
20°FApr 6Apr 2Mar 29Mar 25Mar 22Mar 18Mar 14Mar 10Mar 4
16°FMar 29Mar 22Mar 17Mar 14Mar 10Mar 7Mar 4Feb 28Feb 24

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 28Oct 2Oct 5Oct 7Oct 10Oct 12Oct 15Oct 19
32°FOct 2Oct 8Oct 11Oct 14Oct 17Oct 20Oct 23Oct 26Oct 30
28°FOct 11Oct 17Oct 21Oct 24Oct 27Oct 30Nov 1Nov 4Nov 8
24°FOct 22Oct 27Oct 30Nov 2Nov 4Nov 7Nov 9Nov 13Nov 18
20°FOct 30Nov 3Nov 6Nov 10Nov 13Nov 17Nov 20Nov 24Nov 30
16°FNov 5Nov 10Nov 15Nov 19Nov 22Nov 25Nov 30Dec 4Dec 11

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°F181174169165161158154150143
32°F199192188184180176171167159
28°F220212207203200196192187179
24°F239231225220216212207203196
20°F259251245240235231226220213
16°F278272266261256250246240231

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
5,560
Cooling degree days, base 65°F
1,290
Growing degree days, base 40°F
6,142
Growing degree days, base 45°F
4,925
Growing degree days, base 50°F
3,834
Growing degree days, base 55°F
2,863
Growing degree days, base 60°F
2,014

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,19900
February94907
March717251
April37712169
May12095446
June9274715
July1405869
August3337800
September65145531
October34019209
November713034
December1,06803

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 0.9 km from Horton. Low ground, valleys and open fields freeze earlier and later than a town center or a hillside.

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Sources

NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USC00143810 (Horton). Public domain.