Casey County climate

Casey County Frost Dates and Growing Season

NOAA 1991-2020 normals for Bradfordsville, 27.6 km from Casey County, elevation 660 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Bradfordsville. 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 22 and the first fall freeze around October 20, a growing season of about 180 days.

Median at 36°F
last May 2, first October 10
Median at 32°F
last April 22, first October 20
Median at 28°F
last April 11, first October 30

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 19May 12May 7May 4May 2Apr 29Apr 26Apr 23Apr 19
32°FMay 9May 3Apr 30Apr 26Apr 22Apr 20Apr 17Apr 13Apr 8
28°FApr 30Apr 22Apr 18Apr 14Apr 11Apr 7Apr 4Mar 31Mar 26
24°FApr 16Apr 9Apr 4Apr 2Mar 30Mar 27Mar 23Mar 18Mar 10
20°FApr 4Mar 30Mar 26Mar 21Mar 18Mar 14Mar 8Mar 1Feb 23
16°FMar 26Mar 18Mar 13Mar 8Mar 3Feb 28Feb 23Feb 16Feb 8

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

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°F179173168165161158154149142
32°F198192187184180175171167160
28°F221214209205201197192185177
24°F246238232227223219215210201
20°F276266259254248243238232224
16°F305295287280274268261255246

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
4,560
Cooling degree days, base 65°F
1,174
Growing degree days, base 40°F
6,456
Growing degree days, base 45°F
5,109
Growing degree days, base 50°F
3,906
Growing degree days, base 55°F
2,850
Growing degree days, base 60°F
1,939

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January964016
February783017
March626262
April32118208
May10693455
June11234673
July1349814
August2304767
September43146554
October27825249
November585169
December842022

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 27.6 km from Casey 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 USC00150940 (Bradfordsville). Public domain.