Marble climate

Marble Frost Dates and Growing Season

NOAA 1991-2020 normals for Grand Rpds Forest Lab, 17.3 km from Marble, elevation 1310 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Grand Rpds Forest Lab. 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 17 and the first fall freeze around September 24, a growing season of about 130 days.

Median at 36°F
last May 29, first September 15
Median at 32°F
last May 17, first September 24
Median at 28°F
last May 6, first October 5

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 26May 23May 20May 16
32°FMay 31May 26May 23May 20May 17May 14May 11May 7May 3
28°FMay 19May 15May 12May 9May 6May 3May 1Apr 28Apr 24
24°FMay 11May 4May 1Apr 29Apr 26Apr 23Apr 20Apr 16Apr 12
20°FApr 29Apr 25Apr 21Apr 18Apr 15Apr 12Apr 9Apr 6Apr 2
16°FApr 21Apr 16Apr 12Apr 9Apr 6Apr 4Apr 2Mar 30Mar 24

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 4Sep 9Sep 12Sep 15Sep 17Sep 20Sep 23Sep 27
32°FSep 10Sep 15Sep 18Sep 21Sep 24Sep 27Sep 29Oct 3Oct 7
28°FSep 20Sep 25Sep 29Oct 1Oct 5Oct 8Oct 12Oct 15Oct 20
24°FOct 1Oct 6Oct 11Oct 15Oct 18Oct 22Oct 25Oct 29Nov 3
20°FOct 16Oct 22Oct 26Oct 30Nov 1Nov 3Nov 6Nov 9Nov 14
16°FOct 28Nov 1Nov 3Nov 6Nov 8Nov 11Nov 15Nov 17Nov 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°F125119114111107103999486
32°F149143138133130126121117110
28°F170164160156152148143138132
24°F194187182177173168164159152
20°F216210205200197193188183175
16°F233226221217212210206202196

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
9,319
Cooling degree days, base 65°F
288
Growing degree days, base 40°F
3,566
Growing degree days, base 45°F
2,658
Growing degree days, base 50°F
1,866
Growing degree days, base 55°F
1,200
Growing degree days, base 60°F
665

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,74500
February1,43100
March1,17502
April741023
May38012163
June11854388
July41120544
August6883481
September27719224
October681040
November1,10702
December1,55600

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 17.3 km from Marble. 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 USC00213303 (Grand Rpds Forest Lab). Public domain.