Vanderburgh County climate

Vanderburgh County Frost Dates and Growing Season

NOAA 1991-2020 normals for Evansville Regional AP, 6.1 km from Vanderburgh County, elevation 400 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Evansville Regional 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 4 and the first fall freeze around October 29, a growing season of about 206 days.

Median at 36°F
last April 16, first October 21
Median at 32°F
last April 4, first October 29
Median at 28°F
last March 25, first November 8

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 2Apr 27Apr 23Apr 19Apr 16Apr 13Apr 10Apr 7Apr 3
32°FApr 19Apr 14Apr 10Apr 7Apr 4Apr 1Mar 30Mar 27Mar 22
28°FApr 8Apr 3Mar 31Mar 28Mar 25Mar 23Mar 19Mar 15Mar 9
24°FMar 28Mar 23Mar 19Mar 16Mar 13Mar 9Mar 5Mar 1Feb 24
20°FMar 18Mar 14Mar 9Mar 6Mar 2Feb 28Feb 23Feb 17Feb 8
16°FMar 11Mar 5Mar 1Feb 25Feb 20Feb 13Feb 8Feb 3Jan 27

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

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°F203196192187183180176171164
32°F225219214210206203198193187
28°F252242237233228224219214208
24°F278270263257252247242236228
20°F303294286281275270264258248
16°F328319310304299293287278270

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
4,340
Cooling degree days, base 65°F
1,525
Growing degree days, base 40°F
6,987
Growing degree days, base 45°F
5,615
Growing degree days, base 50°F
4,385
Growing degree days, base 55°F
3,296
Growing degree days, base 60°F
2,340

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January973011
February769018
March575485
April26129255
May73134526
June4319765
July0425890
August1382846
September34191608
October23739290
November562274
December851018

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 6.1 km from Vanderburgh 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 USW00093817 (Evansville Regional AP). Public domain.