Madison climate

Madison Frost Dates and Growing Season

NOAA 1991-2020 normals for Jackson Intl AP, 16.2 km from Madison, elevation 296 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Jackson Intl AP. 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 14 and the first fall freeze around November 14, a growing season of about 245 days.

Median at 36°F
last March 29, first November 3
Median at 32°F
last March 14, first November 14
Median at 28°F
last February 28, first November 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°FApr 16Apr 9Apr 5Apr 2Mar 29Mar 25Mar 21Mar 15Mar 9
32°FApr 2Mar 27Mar 22Mar 17Mar 14Mar 10Mar 6Feb 28Feb 22
28°FMar 17Mar 12Mar 7Mar 3Feb 28Feb 24Feb 19Feb 12Feb 2
24°FMar 9Mar 2Feb 24Feb 15Feb 9Feb 3Jan 30Jan 23Jan 10
20°FFeb 28Feb 14Feb 4Jan 31Jan 27Jan 21Jan 15Jan 7Dec 30
16°FFeb 14Feb 2Jan 30Jan 25Jan 20Jan 14Jan 9Jan 3Dec 27

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 22Oct 26Oct 29Nov 1Nov 3Nov 6Nov 9Nov 14Nov 20
32°FOct 31Nov 4Nov 7Nov 10Nov 14Nov 18Nov 22Nov 29Dec 4
28°FNov 7Nov 12Nov 18Nov 23Nov 28Dec 1Dec 6Dec 12Dec 26
24°FNov 20Nov 30Dec 5Dec 10Dec 19Dec 25Jan 2Jan 7Jan 18
20°FDec 8Dec 19Dec 26Jan 1Jan 5Jan 8Jan 14Jan 21Feb 4
16°FDec 21Dec 28Jan 2Jan 7Jan 11Jan 16Jan 20Jan 28Feb 5

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°F246235229224219215209204196
32°F275264257251245239234228219
28°F307297289282276270263255246
24°F344332324315307301294285273
20°F365365361352343335330320305
16°F365365365365365365356344332

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
96% of years
20°F or colder
71% of years
16°F or colder
33% 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
2,222
Cooling degree days, base 65°F
2,402
Growing degree days, base 40°F
9,397
Growing degree days, base 45°F
7,716
Growing degree days, base 50°F
6,162
Growing degree days, base 55°F
4,749
Growing degree days, base 60°F
3,491

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January562588
February4049124
March25333277
April9491450
May12258711
June0439889
July0532997
August0522987
September3360807
October87126507
November30820210
December5009114

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 16.2 km from Madison. 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 USW00003940 (Jackson Intl AP). Public domain.