Grant climate

Grant Frost Dates and Growing Season

NOAA 1991-2020 normals for Kent City 2 Sw, 15.5 km from Grant, elevation 840 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Kent City 2 Sw. 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 14 and the first fall freeze around September 29, a growing season of about 135 days.

Median at 36°F
last May 29, first September 18
Median at 32°F
last May 14, first September 29
Median at 28°F
last May 2, first October 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°FJun 13Jun 7Jun 3May 31May 29May 25May 22May 17May 9
32°FMay 31May 26May 22May 18May 14May 10May 6May 3Apr 29
28°FMay 19May 14May 9May 5May 2Apr 30Apr 28Apr 24Apr 20
24°FMay 8May 3Apr 30Apr 26Apr 23Apr 20Apr 18Apr 14Apr 10
20°FApr 28Apr 21Apr 18Apr 15Apr 12Apr 9Apr 5Apr 2Mar 30
16°FApr 16Apr 11Apr 7Apr 4Apr 1Mar 30Mar 26Mar 22Mar 16

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°FAug 30Sep 5Sep 10Sep 14Sep 18Sep 21Sep 24Sep 28Oct 2
32°FSep 14Sep 19Sep 23Sep 26Sep 29Oct 2Oct 4Oct 7Oct 12
28°FSep 24Sep 29Oct 3Oct 5Oct 8Oct 12Oct 14Oct 18Oct 23
24°FOct 4Oct 10Oct 15Oct 19Oct 22Oct 26Oct 29Nov 1Nov 7
20°FOct 21Oct 27Nov 1Nov 3Nov 6Nov 11Nov 15Nov 21Nov 27
16°FNov 5Nov 11Nov 16Nov 20Nov 23Nov 28Dec 1Dec 6Dec 13

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°F1351281231171121071029688
32°F157149144140135131126120113
28°F179171166162158153148143135
24°F205198192187182177171166158
20°F234226220214210205201194186
16°F260252246241237232228221214

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
6,994
Cooling degree days, base 65°F
494
Growing degree days, base 40°F
4,420
Growing degree days, base 45°F
3,370
Growing degree days, base 50°F
2,454
Growing degree days, base 55°F
1,660
Growing degree days, base 60°F
997

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,31100
February1,13501
March976115
April602152
May28324238
June62101490
July16174623
August32139572
September15850349
October4745104
November814010
December1,13000

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 15.5 km from Grant. 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 USC00204320 (Kent City 2 Sw). Public domain.