Edon climate

Edon Frost Dates and Growing Season

NOAA 1991-2020 normals for Montpelier, 12.6 km from Edon, elevation 860 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Montpelier. 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 28 and the first fall freeze around October 18, a growing season of about 173 days.

Median at 36°F
last May 7, first October 6
Median at 32°F
last April 28, first October 18
Median at 28°F
last April 17, first October 31

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 23May 18May 13May 10May 7May 4Apr 30Apr 28Apr 23
32°FMay 12May 7May 4Apr 30Apr 28Apr 24Apr 21Apr 18Apr 15
28°FMay 3Apr 28Apr 22Apr 19Apr 17Apr 14Apr 11Apr 6Apr 2
24°FApr 20Apr 15Apr 11Apr 7Apr 4Apr 2Mar 31Mar 27Mar 20
20°FApr 8Apr 3Mar 31Mar 29Mar 26Mar 22Mar 19Mar 14Mar 8
16°FMar 31Mar 27Mar 22Mar 19Mar 15Mar 12Mar 8Mar 5Feb 28

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 1Oct 4Oct 6Oct 9Oct 11Oct 14Oct 20
32°FOct 4Oct 8Oct 12Oct 15Oct 18Oct 21Oct 24Oct 28Nov 1
28°FOct 16Oct 21Oct 25Oct 28Oct 31Nov 1Nov 5Nov 8Nov 13
24°FOct 28Nov 1Nov 4Nov 6Nov 10Nov 13Nov 17Nov 21Nov 26
20°FNov 7Nov 11Nov 15Nov 18Nov 22Nov 26Nov 30Dec 4Dec 10
16°FNov 15Nov 21Nov 26Nov 30Dec 3Dec 7Dec 11Dec 16Dec 23

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°F171164160156152148144138133
32°F193187182177173169165159151
28°F215209204200196192187183175
24°F244235229225221216211206199
20°F266258252247244239234228221
16°F287279273268263258254248240

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
6,460
Cooling degree days, base 65°F
706
Growing degree days, base 40°F
4,975
Growing degree days, base 45°F
3,861
Growing degree days, base 50°F
2,876
Growing degree days, base 55°F
2,020
Growing degree days, base 60°F
1,293

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,26901
February1,07901
March903119
April524584
May22344301
June41158567
July5236696
August13184635
September11472413
October4228139
November770020
December1,09702

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 12.6 km from Edon. 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 USC00335438 (Montpelier). Public domain.