Hancock County climate

Hancock County Frost Dates and Growing Season

NOAA 1991-2020 normals for Cannelton, 8.9 km from Hancock County, elevation 402 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Cannelton. 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 2 and the first fall freeze around November 7, a growing season of about 218 days.

Median at 36°F
last April 16, first October 30
Median at 32°F
last April 2, first November 7
Median at 28°F
last March 21, first November 17

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 1Apr 26Apr 21Apr 18Apr 16Apr 13Apr 9Apr 6Mar 31
32°FApr 20Apr 14Apr 9Apr 6Apr 2Mar 31Mar 27Mar 22Mar 16
28°FApr 8Apr 2Mar 30Mar 25Mar 21Mar 16Mar 12Mar 7Feb 28
24°FMar 27Mar 20Mar 15Mar 11Mar 7Mar 2Feb 27Feb 21Feb 14
20°FMar 14Mar 8Mar 4Feb 28Feb 25Feb 20Feb 15Feb 10Feb 4
16°FMar 5Feb 27Feb 20Feb 15Feb 11Feb 6Feb 2Jan 28Jan 19

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

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°F216210205201196193188183176
32°F240233227222218214210205197
28°F266258251246241237231226218
24°F291283276270265259253246238
20°F319308300294288283277270260
16°F341332325319311305300293282

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
99% 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
4,217
Cooling degree days, base 65°F
1,450
Growing degree days, base 40°F
6,971
Growing degree days, base 45°F
5,575
Growing degree days, base 50°F
4,329
Growing degree days, base 55°F
3,236
Growing degree days, base 60°F
2,277

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January94809
February755016
March590377
April26520244
May80121506
June4278724
July0400865
August1372837
September23204631
October20048328
November530379
December822014

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 8.9 km from Hancock County. 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 USC00121256 (Cannelton). Public domain.