Pine Bluffs climate

Pine Bluffs Frost Dates and Growing Season

NOAA 1991-2020 normals for Pine Bluffs 1ESE, 1 km from Pine Bluffs, elevation 5058 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Pine Bluffs 1ESE. 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 10 and the first fall freeze around October 1, a growing season of about 142 days.

Median at 36°F
last May 21, first September 21
Median at 32°F
last May 10, first October 1
Median at 28°F
last May 1, 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°FJun 4May 30May 26May 23May 21May 19May 16May 13May 9
32°FMay 24May 18May 15May 12May 10May 8May 5May 3Apr 30
28°FMay 12May 9May 6May 3May 1Apr 30Apr 27Apr 24Apr 18
24°FMay 5May 1Apr 27Apr 24Apr 21Apr 18Apr 15Apr 11Apr 6
20°FApr 25Apr 20Apr 16Apr 13Apr 10Apr 6Apr 2Mar 29Mar 23
16°FApr 16Apr 9Apr 4Mar 31Mar 27Mar 23Mar 18Mar 12Mar 7

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 8Sep 13Sep 16Sep 18Sep 21Sep 23Sep 25Sep 28Oct 3
32°FSep 17Sep 22Sep 26Sep 28Oct 1Oct 3Oct 6Oct 9Oct 13
28°FSep 25Sep 30Oct 4Oct 7Oct 10Oct 13Oct 16Oct 19Oct 23
24°FOct 4Oct 11Oct 14Oct 18Oct 21Oct 23Oct 26Oct 30Nov 3
20°FOct 15Oct 21Oct 24Oct 28Nov 1Nov 3Nov 6Nov 10Nov 15
16°FOct 23Oct 30Nov 2Nov 5Nov 9Nov 12Nov 15Nov 19Nov 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°F138133129125121117113109103
32°F159153149145142138134129122
28°F178172168163160156151147140
24°F200193188183179175171166158
20°F225218211206202197193187180
16°F250242236230225220214208201

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
6,619
Cooling degree days, base 65°F
518
Growing degree days, base 40°F
4,453
Growing degree days, base 45°F
3,364
Growing degree days, base 50°F
2,439
Growing degree days, base 55°F
1,659
Growing degree days, base 60°F
1,016

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,10501
February97402
March840011
April616038
May33412203
June6876459
July7219677
August25170610
September16439339
October524192
November84007
December1,12200

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 1 km from Pine Bluffs. 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 USC00487236 (Pine Bluffs 1ESE). Public domain.