Walton climate

Walton Frost Dates and Growing Season

NOAA 1991-2020 normals for Young America, 14 km from Walton, elevation 773 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Young America. 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 25 and the first fall freeze around October 17, a growing season of about 174 days.

Median at 36°F
last May 5, first October 4
Median at 32°F
last April 25, first October 17
Median at 28°F
last April 14, first October 28

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 21May 15May 12May 8May 5May 1Apr 29Apr 26Apr 22
32°FMay 11May 5May 1Apr 28Apr 25Apr 22Apr 19Apr 16Apr 11
28°FMay 1Apr 24Apr 20Apr 16Apr 14Apr 10Apr 7Apr 3Mar 31
24°FApr 17Apr 12Apr 7Apr 3Apr 1Mar 30Mar 25Mar 21Mar 15
20°FApr 5Apr 1Mar 29Mar 24Mar 20Mar 17Mar 14Mar 9Mar 4
16°FMar 29Mar 23Mar 18Mar 15Mar 12Mar 8Mar 5Mar 1Feb 21

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 21Sep 26Sep 29Oct 1Oct 4Oct 7Oct 9Oct 12Oct 17
32°FOct 1Oct 6Oct 11Oct 13Oct 17Oct 19Oct 22Oct 26Nov 1
28°FOct 13Oct 18Oct 22Oct 25Oct 28Oct 31Nov 2Nov 7Nov 13
24°FOct 27Nov 1Nov 2Nov 7Nov 10Nov 13Nov 18Nov 23Nov 29
20°FNov 7Nov 12Nov 16Nov 20Nov 23Nov 27Dec 1Dec 5Dec 12
16°FNov 14Nov 21Nov 25Nov 30Dec 3Dec 7Dec 11Dec 16Dec 21

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°F171165160156151147144138131
32°F194186181177174170164159151
28°F218211207202197193188183173
24°F246239233228223218213208198
20°F269261257252246241236230223
16°F292283276271266261255249240

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
6,177
Cooling degree days, base 65°F
771
Growing degree days, base 40°F
5,244
Growing degree days, base 45°F
4,086
Growing degree days, base 50°F
3,063
Growing degree days, base 55°F
2,166
Growing degree days, base 60°F
1,398

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,26501
February1,04002
March842129
April4768112
May18462357
June30180600
July7233691
August14186637
September10686434
October38816169
November738028
December1,09003

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 14 km from Walton. 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 USC00129905 (Young America). Public domain.