Plankinton climate

Plankinton Frost Dates and Growing Season

NOAA 1991-2020 normals for White Lake, 15.3 km from Plankinton, elevation 1629 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for White Lake. 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 May 3 and the first fall freeze around October 5, a growing season of about 153 days.

Median at 36°F
last May 12, first September 27
Median at 32°F
last May 3, first October 5
Median at 28°F
last April 25, first October 14

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 27May 21May 17May 14May 12May 10May 7May 5May 2
32°FMay 17May 11May 7May 5May 3May 1Apr 29Apr 25Apr 20
28°FMay 7May 3Apr 30Apr 28Apr 25Apr 21Apr 18Apr 15Apr 11
24°FApr 30Apr 25Apr 21Apr 18Apr 16Apr 13Apr 10Apr 7Apr 3
20°FApr 21Apr 16Apr 12Apr 9Apr 7Apr 4Apr 2Mar 29Mar 21
16°FApr 13Apr 8Apr 4Apr 1Mar 30Mar 26Mar 22Mar 17Mar 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 15Sep 19Sep 22Sep 25Sep 27Sep 29Oct 1Oct 4Oct 9
32°FSep 21Sep 27Sep 30Oct 2Oct 5Oct 8Oct 11Oct 14Oct 18
28°FSep 29Oct 4Oct 7Oct 11Oct 14Oct 17Oct 20Oct 23Oct 27
24°FOct 8Oct 14Oct 18Oct 21Oct 23Oct 26Oct 29Nov 2Nov 6
20°FOct 19Oct 23Oct 26Oct 29Nov 1Nov 3Nov 6Nov 10Nov 15
16°FOct 26Oct 31Nov 2Nov 5Nov 8Nov 11Nov 14Nov 19Nov 24

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°F153148143140136133130124117
32°F170163159156153150146141135
28°F188182177173170166161156151
24°F207201197192188185180176168
20°F228221215211207204200195188
16°F246238232227223219215210204

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
7,584
Cooling degree days, base 65°F
743
Growing degree days, base 40°F
4,733
Growing degree days, base 45°F
3,695
Growing degree days, base 50°F
2,777
Growing degree days, base 55°F
1,976
Growing degree days, base 60°F
1,296

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,46800
February1,20801
March997010
April603161
May26828260
June47136539
July6281741
August19214660
September14377394
October5346102
November94809
December1,34400

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 15.3 km from Plankinton. 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 USC00399232 (White Lake). Public domain.