Hancock County climate

Hancock County Frost Dates and Growing Season

NOAA 1991-2020 normals for Bentley, 8 km from Hancock County, elevation 650 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Bentley. 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 13 and the first fall freeze around October 22, a growing season of about 191 days.

Median at 36°F
last April 25, first October 12
Median at 32°F
last April 13, first October 22
Median at 28°F
last April 3, first November 1

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 10May 5May 1Apr 29Apr 25Apr 22Apr 18Apr 15Apr 11
32°FApr 30Apr 24Apr 20Apr 16Apr 13Apr 10Apr 8Apr 4Mar 30
28°FApr 20Apr 13Apr 9Apr 6Apr 3Apr 1Mar 29Mar 23Mar 18
24°FApr 8Apr 3Mar 31Mar 28Mar 23Mar 20Mar 16Mar 12Mar 7
20°FMar 31Mar 25Mar 21Mar 17Mar 14Mar 11Mar 7Mar 3Feb 27
16°FMar 23Mar 17Mar 13Mar 10Mar 5Mar 3Feb 28Feb 24Feb 17

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 25Oct 1Oct 6Oct 9Oct 12Oct 15Oct 18Oct 21Oct 25
32°FOct 8Oct 14Oct 17Oct 20Oct 22Oct 25Oct 27Oct 30Nov 4
28°FOct 20Oct 24Oct 27Oct 30Nov 1Nov 3Nov 6Nov 10Nov 15
24°FOct 28Nov 2Nov 5Nov 8Nov 11Nov 14Nov 17Nov 21Nov 28
20°FNov 6Nov 10Nov 14Nov 18Nov 21Nov 25Nov 29Dec 3Dec 8
16°FNov 12Nov 19Nov 24Nov 27Dec 1Dec 5Dec 9Dec 13Dec 19

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°F188182178174170165161156149
32°F210203198194191188183177170
28°F233226221216212208204199191
24°F255249242237232228223218211
20°F276268262257253249244238229
16°F295287281276271266260255247

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
5,590
Cooling degree days, base 65°F
1,170
Growing degree days, base 40°F
6,007
Growing degree days, base 45°F
4,782
Growing degree days, base 50°F
3,692
Growing degree days, base 55°F
2,725
Growing degree days, base 60°F
1,880

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,21501
February97105
March734247
April38316168
May13489425
June12255693
July1355818
August4294755
September71135517
October33224216
November689144
December1,04304

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 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 USC00110598 (Bentley). Public domain.