Shadeland climate

Shadeland Frost Dates and Growing Season

NOAA 1991-2020 normals for Lafayette Purdue Univ AP, 4.4 km from Shadeland, elevation 599 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Lafayette Purdue Univ AP. 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 26 and the first fall freeze around October 18, a growing season of about 173 days.

Median at 36°F
last May 7, first October 7
Median at 32°F
last April 26, first October 18
Median at 28°F
last April 13, first October 28

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

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

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°F172165160156152149145140133
32°F192185180177173169165159152
28°F216209205200196192187182174
24°F244236231226221217213207200
20°F268259254249244239235229223
16°F291282276271265260254248240

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
5,824
Cooling degree days, base 65°F
883
Growing degree days, base 40°F
5,539
Growing degree days, base 45°F
4,342
Growing degree days, base 50°F
3,277
Growing degree days, base 55°F
2,344
Growing degree days, base 60°F
1,541

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,21502
February98804
March779241
April4258132
May17064369
June24193619
July3270732
August7230688
September83100469
October36516180
November711036
December1,05405

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 4.4 km from Shadeland. 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 USW00014835 (Lafayette Purdue Univ AP). Public domain.