McClusky climate

McClusky Frost Dates and Growing Season

NOAA 1991-2020 normals for Mc Clusky, 0.4 km from McClusky, elevation 1927 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Mc Clusky. 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 8 and the first fall freeze around October 1, a growing season of about 145 days.

Median at 36°F
last May 17, first September 23
Median at 32°F
last May 8, first October 1
Median at 28°F
last April 30, first October 10

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 30May 25May 22May 19May 17May 15May 12May 9May 5
32°FMay 20May 16May 13May 10May 8May 5May 3Apr 30Apr 25
28°FMay 11May 8May 4May 2Apr 30Apr 26Apr 23Apr 19Apr 14
24°FMay 2Apr 28Apr 24Apr 21Apr 18Apr 15Apr 12Apr 9Apr 5
20°FApr 25Apr 19Apr 15Apr 12Apr 9Apr 7Apr 4Apr 2Mar 29
16°FApr 17Apr 11Apr 8Apr 5Apr 3Apr 1Mar 29Mar 24Mar 18

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 11Sep 16Sep 19Sep 21Sep 23Sep 25Sep 28Sep 30Oct 3
32°FSep 19Sep 23Sep 26Sep 29Oct 1Oct 3Oct 6Oct 9Oct 13
28°FSep 27Oct 1Oct 4Oct 7Oct 10Oct 12Oct 15Oct 18Oct 22
24°FOct 5Oct 10Oct 13Oct 16Oct 18Oct 21Oct 24Oct 27Nov 1
20°FOct 14Oct 19Oct 21Oct 25Oct 27Oct 30Nov 1Nov 4Nov 9
16°FOct 23Oct 27Oct 30Nov 1Nov 4Nov 7Nov 9Nov 13Nov 18

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°F144138134131127124121116110
32°F162156152149145142138133127
28°F182176170167163159155150144
24°F202195191187183179175171164
20°F219211208204200196192187180
16°F235227222218215211207202195

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
8,290
Cooling degree days, base 65°F
655
Growing degree days, base 40°F
4,491
Growing degree days, base 45°F
3,501
Growing degree days, base 50°F
2,616
Growing degree days, base 55°F
1,840
Growing degree days, base 60°F
1,181

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,61200
February1,35000
March1,11005
April621154
May26526260
June58115508
July11238693
August21211656
September16461360
October581378
November1,03804
December1,46200

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 0.4 km from McClusky. 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 USC00325710 (Mc Clusky). Public domain.