Avon climate

Avon Frost Dates and Growing Season

NOAA 1991-2020 normals for Frisco 2NNE, 14.1 km from Avon, elevation 0 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Frisco 2NNE. 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 1 and the first fall freeze around December 20, a growing season of about 292 days.

Median at 36°F
last March 17, first December 1
Median at 32°F
last March 1, first December 20
Median at 28°F
last February 11, first January 4

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°FMar 31Mar 28Mar 24Mar 20Mar 17Mar 13Mar 9Mar 3Feb 26
32°FMar 21Mar 15Mar 9Mar 5Mar 1Feb 26Feb 21Feb 12Feb 3
28°FMar 7Feb 28Feb 24Feb 17Feb 11Feb 4Jan 31Jan 26Jan 14
24°FFeb 24Feb 14Feb 8Feb 1Jan 30Jan 25Jan 19Jan 12Jan 4
20°FFeb 17Feb 6Feb 1Jan 31Jan 27Jan 22Jan 17Jan 11Jan 5
16°FFeb 11Feb 5Jan 30Jan 27Jan 23Jan 18Jan 14Jan 10Jan 5

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°FNov 16Nov 21Nov 26Nov 29Dec 1Dec 5Dec 9Dec 14Dec 24
32°FNov 28Dec 3Dec 9Dec 14Dec 20Dec 26Jan 1Jan 4Jan 12
28°FDec 11Dec 21Dec 27Jan 1Jan 4Jan 9Jan 14Jan 20Jan 31
24°FDec 26Jan 1Jan 6Jan 9Jan 14Jan 19Jan 24Jan 30Feb 6
20°FJan 3Jan 8Jan 13Jan 17Jan 21Jan 26Jan 29Feb 1Feb 8
16°FJan 5Jan 8Jan 13Jan 17Jan 19Jan 25Jan 28Feb 2Feb 9

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°F289280273267261256251244237
32°F319309302297292286281274262
28°F354339333325318311306300291
24°F365365365358348338334325313
20°F365365365365365365362344332
16°F365365365365365365365365362

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
94% of years
24°F or colder
70% of years
20°F or colder
33% of years
16°F or colder
11% 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
2,235
Cooling degree days, base 65°F
2,062
Growing degree days, base 40°F
9,031
Growing degree days, base 45°F
7,326
Growing degree days, base 50°F
5,747
Growing degree days, base 55°F
4,325
Growing degree days, base 60°F
3,099

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January562173
February452184
March3517168
April13845362
May21176620
June0374823
July0487952
August0479944
September2344792
October51122536
November22422262
December4344131

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 14.1 km from Avon. 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 USC00313336 (Frisco 2NNE). Public domain.