Fairplay climate

Fairplay Frost Dates and Growing Season

NOAA 1991-2020 normals for Fairplay S Park Rd, 0.8 km from Fairplay, elevation 9996 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Fairplay S Park Rd. 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 June 16 and the first fall freeze around September 9, a growing season of about 83 days.

Median at 32°F
last June 16, first September 9
Median at 28°F
last June 2, first September 21

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°F–––––––––
32°FJun 30Jun 26Jun 23Jun 20Jun 16Jun 13Jun 10Jun 7Jun 2
28°FJun 17Jun 12Jun 8Jun 5Jun 2May 31May 28May 24May 21
24°FJun 2May 28May 24May 22May 19May 17May 14May 10May 5
20°FMay 22May 18May 13May 10May 8May 5May 2Apr 30Apr 25
16°FMay 13May 8May 4May 1Apr 28Apr 25Apr 21Apr 17Apr 12

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°F–––––––––
32°FAug 21Aug 29Sep 2Sep 5Sep 9Sep 12Sep 15Sep 19Sep 24
28°FSep 6Sep 11Sep 14Sep 18Sep 21Sep 23Sep 26Sep 29Oct 3
24°FSep 16Sep 21Sep 24Sep 27Sep 29Oct 2Oct 5Oct 9Oct 14
20°FSep 25Sep 30Oct 3Oct 7Oct 10Oct 13Oct 16Oct 20Oct 25
16°FOct 4Oct 10Oct 15Oct 18Oct 20Oct 23Oct 26Oct 31Nov 5

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°F696156514743383530
32°F1019590878378746963
28°F126120116112107103999487
24°F153147141138134129125119112
20°F175168163159156151147141134
16°F196189185180176171166161154

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
10,316
Cooling degree days, base 65°F
0
Growing degree days, base 40°F
1,795
Growing degree days, base 45°F
1,066
Growing degree days, base 50°F
505
Growing degree days, base 55°F
148
Growing degree days, base 60°F
16

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,38700
February1,25700
March1,18300
April95400
May71909
June414085
July2580210
August3210154
September498045
October82503
November1,11200
December1,38900

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 0.8 km from Fairplay. 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 USC00052816 (Fairplay S Park Rd). Public domain.