Hart climate

Hart Frost Dates and Growing Season

NOAA 1991-2020 normals for Hart 3 Wsw, 5.5 km from Hart, elevation 770 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Hart 3 Wsw. 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 12 and the first fall freeze around October 10, a growing season of about 151 days.

Median at 36°F
last May 24, first September 29
Median at 32°F
last May 12, first October 10
Median at 28°F
last April 30, first October 25

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°FJun 6Jun 1May 30May 27May 24May 21May 17May 12May 7
32°FMay 28May 24May 20May 16May 12May 8May 4Apr 30Apr 25
28°FMay 20May 13May 8May 4Apr 30Apr 28Apr 23Apr 19Apr 14
24°FMay 8May 1Apr 27Apr 21Apr 18Apr 15Apr 10Apr 5Mar 31
20°FApr 26Apr 17Apr 11Apr 7Apr 4Apr 1Mar 29Mar 24Mar 19
16°FApr 8Apr 3Mar 31Mar 28Mar 24Mar 21Mar 18Mar 15Mar 8

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 14Sep 19Sep 23Sep 26Sep 29Oct 1Oct 4Oct 7Oct 13
32°FSep 25Sep 30Oct 3Oct 6Oct 10Oct 13Oct 16Oct 20Oct 26
28°FOct 8Oct 13Oct 18Oct 22Oct 25Oct 29Nov 1Nov 3Nov 7
24°FOct 22Oct 28Nov 1Nov 4Nov 7Nov 10Nov 14Nov 19Nov 24
20°FNov 5Nov 11Nov 15Nov 19Nov 22Nov 26Nov 29Dec 2Dec 8
16°FNov 18Nov 23Nov 28Dec 1Dec 3Dec 6Dec 11Dec 16Dec 22

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°F150142136132128123119113106
32°F174167161156151146141136129
28°F199190184179174169164158151
24°F228219212206202197191185176
20°F256247241236230225219214204
16°F277270264259254249245239232

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
7,210
Cooling degree days, base 65°F
415
Growing degree days, base 40°F
4,178
Growing degree days, base 45°F
3,155
Growing degree days, base 50°F
2,267
Growing degree days, base 55°F
1,506
Growing degree days, base 60°F
879

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,30700
February1,14500
March1,011111
April636044
May33319205
June8480447
July30147583
August39119546
September17346333
October501391
November81808
December1,13501

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 5.5 km from Hart. 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 USC00203632 (Hart 3 Wsw). Public domain.