Addison climate

Addison Frost Dates and Growing Season

NOAA 1991-2020 normals for Addison, 5.9 km from Addison, elevation 818 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Addison. 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 4 and the first fall freeze around November 1, a growing season of about 210 days.

Median at 36°F
last April 16, first October 23
Median at 32°F
last April 4, first November 1
Median at 28°F
last March 22, first November 13

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 2Apr 28Apr 24Apr 19Apr 16Apr 13Apr 9Apr 5Mar 30
32°FApr 24Apr 17Apr 12Apr 8Apr 4Apr 1Mar 28Mar 22Mar 14
28°FApr 10Apr 4Mar 31Mar 27Mar 22Mar 17Mar 13Mar 9Feb 28
24°FMar 29Mar 22Mar 16Mar 12Mar 8Mar 4Feb 28Feb 23Feb 16
20°FMar 15Mar 9Mar 4Feb 28Feb 24Feb 20Feb 13Feb 6Jan 30
16°FMar 6Feb 28Feb 21Feb 13Feb 7Feb 2Jan 29Jan 19Jan 8

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°FOct 10Oct 15Oct 19Oct 21Oct 23Oct 26Oct 29Nov 1Nov 5
32°FOct 20Oct 23Oct 27Oct 30Nov 1Nov 4Nov 7Nov 11Nov 17
28°FOct 30Nov 2Nov 5Nov 9Nov 13Nov 16Nov 21Nov 27Dec 4
24°FNov 8Nov 13Nov 18Nov 22Nov 27Dec 1Dec 5Dec 10Dec 22
20°FNov 17Nov 24Dec 1Dec 5Dec 9Dec 16Dec 25Jan 1Jan 8
16°FNov 28Dec 6Dec 16Dec 25Dec 31Jan 3Jan 7Jan 15Jan 28

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°F211203198194190186181176169
32°F235227220215210206202196188
28°F265255249243237232226219211
24°F295284276271264258252245233
20°F324311304297291284277269258
16°F357341332325318311306296284

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
93% 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
3,397
Cooling degree days, base 65°F
1,475
Growing degree days, base 40°F
7,534
Growing degree days, base 45°F
6,013
Growing degree days, base 50°F
4,640
Growing degree days, base 55°F
3,420
Growing degree days, base 60°F
2,363

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January778035
February607142
March4227150
April20029298
May58129537
June1277726
July0397862
August0366831
September21216645
October17747351
November4456116
December688149

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 5.9 km from Addison. 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 USC00010063 (Addison). Public domain.