Cannon County climate

Cannon County Frost Dates and Growing Season

NOAA 1991-2020 normals for Woodbury 1 Wnw, 4 km from Cannon County, elevation 750 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Woodbury 1 Wnw. 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 17 and the first fall freeze around October 21, a growing season of about 184 days.

Median at 36°F
last April 30, first October 12
Median at 32°F
last April 17, first October 21
Median at 28°F
last April 5, first October 29

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 14May 9May 5May 2Apr 30Apr 27Apr 23Apr 20Apr 15
32°FMay 2Apr 27Apr 23Apr 20Apr 17Apr 15Apr 12Apr 8Apr 3
28°FApr 21Apr 16Apr 12Apr 9Apr 5Apr 3Mar 30Mar 25Mar 19
24°FApr 11Apr 4Apr 1Mar 28Mar 24Mar 21Mar 16Mar 10Mar 3
20°FMar 31Mar 24Mar 19Mar 15Mar 9Mar 3Feb 27Feb 22Feb 13
16°FMar 18Mar 11Mar 4Feb 28Feb 23Feb 17Feb 10Feb 3Jan 26

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 30Oct 4Oct 7Oct 10Oct 12Oct 15Oct 18Oct 21Oct 25
32°FOct 8Oct 12Oct 15Oct 18Oct 21Oct 23Oct 26Oct 29Nov 3
28°FOct 16Oct 21Oct 24Oct 26Oct 29Nov 1Nov 3Nov 6Nov 11
24°FOct 26Oct 30Nov 2Nov 5Nov 8Nov 12Nov 15Nov 19Nov 26
20°FNov 4Nov 9Nov 14Nov 17Nov 22Nov 26Dec 1Dec 4Dec 13
16°FNov 12Nov 20Nov 27Dec 1Dec 5Dec 11Dec 20Dec 28Jan 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°F183176171167163160156151144
32°F205198193188184180175170163
28°F228219214209205201196192185
24°F256245238232227223218213205
20°F288276268261255249243236227
16°F324309300292285277269261251

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
3,796
Cooling degree days, base 65°F
1,429
Growing degree days, base 40°F
7,199
Growing degree days, base 45°F
5,731
Growing degree days, base 50°F
4,417
Growing degree days, base 55°F
3,262
Growing degree days, base 60°F
2,271

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January834126
February659133
March4995109
April24427264
May77114503
June5285730
July0391856
August1363828
September28197620
October21542314
November500497
December734138

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 4 km from Cannon County. 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 USC00409866 (Woodbury 1 Wnw). Public domain.