Miami County climate

Miami County Frost Dates and Growing Season

NOAA 1991-2020 normals for Paola, 4.6 km from Miami County, elevation 860 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Paola. 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 21, a growing season of about 191 days.

Median at 36°F
last April 25, first October 13
Median at 32°F
last April 13, first October 21
Median at 28°F
last April 3, first October 31

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 6May 3Apr 30Apr 27Apr 25Apr 22Apr 19Apr 15Apr 11
32°FApr 28Apr 23Apr 19Apr 16Apr 13Apr 10Apr 7Apr 4Mar 31
28°FApr 18Apr 12Apr 9Apr 6Apr 3Mar 31Mar 29Mar 23Mar 16
24°FApr 7Apr 2Mar 30Mar 27Mar 23Mar 20Mar 16Mar 11Mar 5
20°FMar 31Mar 25Mar 21Mar 16Mar 12Mar 9Mar 5Mar 1Feb 25
16°FMar 20Mar 15Mar 10Mar 7Mar 4Mar 1Feb 26Feb 22Feb 12

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 4Oct 7Oct 9Oct 13Oct 15Oct 18Oct 21Oct 26
32°FOct 8Oct 13Oct 17Oct 19Oct 21Oct 24Oct 27Oct 31Nov 3
28°FOct 17Oct 22Oct 25Oct 29Oct 31Nov 2Nov 5Nov 8Nov 14
24°FOct 28Nov 1Nov 4Nov 6Nov 10Nov 13Nov 17Nov 23Nov 28
20°FNov 3Nov 8Nov 12Nov 16Nov 20Nov 24Nov 29Dec 2Dec 7
16°FNov 11Nov 17Nov 23Nov 28Dec 1Dec 4Dec 7Dec 11Dec 18

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°F190183178174171167163158152
32°F210203198195191188183177171
28°F233224220215211206203198191
24°F258248242236232227223217208
20°F277269264258253247242236227
16°F297289282275270265261254246

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
4,999
Cooling degree days, base 65°F
1,385
Growing degree days, base 40°F
6,506
Growing degree days, base 45°F
5,222
Growing degree days, base 50°F
4,072
Growing degree days, base 55°F
3,043
Growing degree days, base 60°F
2,147

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,10501
February86109
March645264
April32917199
May92102476
June6286730
July0426891
August2363826
September53161559
October28527252
November627159
December99507

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 4.6 km from Miami 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 USC00146209 (Paola). Public domain.