Addison climate

Addison Frost Dates and Growing Season

NOAA 1991-2020 normals for Tipton 2WNW, 20.1 km from Addison, elevation 970 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Tipton 2WNW. 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 May 5 and the first fall freeze around October 10, a growing season of about 157 days.

Median at 36°F
last May 18, first October 1
Median at 32°F
last May 5, first October 10
Median at 28°F
last April 26, first October 22

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°FJun 2May 29May 25May 22May 18May 14May 10May 7May 2
32°FMay 23May 17May 13May 9May 5May 2Apr 30Apr 26Apr 22
28°FMay 11May 5May 1Apr 29Apr 26Apr 23Apr 20Apr 17Apr 13
24°FApr 30Apr 24Apr 21Apr 18Apr 15Apr 12Apr 9Apr 6Apr 2
20°FApr 18Apr 13Apr 9Apr 6Apr 4Apr 2Mar 31Mar 25Mar 20
16°FApr 8Apr 4Apr 1Mar 29Mar 25Mar 21Mar 18Mar 15Mar 10

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 18Sep 22Sep 25Sep 28Oct 1Oct 2Oct 5Oct 7Oct 11
32°FSep 28Oct 2Oct 5Oct 8Oct 10Oct 13Oct 16Oct 19Oct 23
28°FOct 9Oct 14Oct 17Oct 20Oct 22Oct 25Oct 27Oct 30Nov 3
24°FOct 20Oct 26Oct 29Oct 31Nov 2Nov 5Nov 8Nov 11Nov 15
20°FNov 1Nov 3Nov 7Nov 10Nov 13Nov 16Nov 19Nov 23Nov 27
16°FNov 9Nov 13Nov 17Nov 20Nov 23Nov 27Nov 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°F155148143140135131126122115
32°F175170164160157153149144134
28°F197191186182178174170164157
24°F219213208204201197192187179
20°F242234230226222218215210203
16°F266259252247243239235230222

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
6,884
Cooling degree days, base 65°F
538
Growing degree days, base 40°F
4,588
Growing degree days, base 45°F
3,519
Growing degree days, base 50°F
2,582
Growing degree days, base 55°F
1,764
Growing degree days, base 60°F
1,074

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,31700
February1,13400
March951011
April579163
May26226253
June54112509
July12189642
August18149597
September12854382
October4705112
November816012
December1,14401

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 20.1 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 USC00208202 (Tipton 2WNW). Public domain.