Humphrey climate

Humphrey Frost Dates and Growing Season

NOAA 1991-2020 normals for Stuttgart 9 Ese, 27.1 km from Humphrey, elevation 198 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Stuttgart 9 Ese. 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 March 11 and the first fall freeze around November 17, a growing season of about 250 days.

Median at 36°F
last March 23, first November 5
Median at 32°F
last March 11, first November 17
Median at 28°F
last February 28, first December 1

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°FApr 9Apr 4Mar 31Mar 28Mar 23Mar 19Mar 16Mar 11Mar 4
32°FMar 31Mar 24Mar 18Mar 15Mar 11Mar 7Mar 3Feb 28Feb 21
28°FMar 19Mar 13Mar 8Mar 4Feb 28Feb 25Feb 19Feb 11Feb 2
24°FMar 9Mar 2Feb 26Feb 21Feb 14Feb 7Feb 1Jan 27Jan 14
20°FFeb 28Feb 18Feb 9Feb 2Jan 29Jan 23Jan 18Jan 11Jan 1
16°FFeb 19Feb 8Feb 1Jan 28Jan 22Jan 17Jan 12Jan 6Dec 31

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 23Oct 27Oct 31Nov 2Nov 5Nov 9Nov 13Nov 17Nov 22
32°FOct 31Nov 5Nov 9Nov 13Nov 17Nov 21Nov 26Dec 1Dec 6
28°FNov 8Nov 15Nov 21Nov 27Dec 1Dec 5Dec 11Dec 20Dec 30
24°FNov 23Dec 2Dec 9Dec 17Dec 25Dec 29Jan 2Jan 8Jan 18
20°FDec 8Dec 17Dec 25Dec 30Jan 4Jan 8Jan 15Jan 22Feb 1
16°FDec 15Dec 28Jan 2Jan 7Jan 12Jan 17Jan 23Feb 1Feb 9

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°F250242235230226222217210203
32°F275267261255250244238232224
28°F310299291283276270262256245
24°F346333325317311304296286273
20°F365364355346340333326316304
16°F365365365365365359350342328

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
97% of years
20°F or colder
82% of years
16°F or colder
48% 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
2,886
Cooling degree days, base 65°F
2,236
Growing degree days, base 40°F
8,684
Growing degree days, base 45°F
7,096
Growing degree days, base 50°F
5,652
Growing degree days, base 55°F
4,359
Growing degree days, base 60°F
3,221

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January720132
February534263
March35314192
April12970400
May19240687
June0443892
July05381,003
August0502967
September9316757
October11999451
November37512158
December630150

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 27.1 km from Humphrey. Low ground, valleys and open fields freeze earlier and later than a town center or a hillside.

More

Sources

NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal normals for station USC00036920 (Stuttgart 9 Ese). Public domain.