Crook County climate

Crook County Frost Dates and Growing Season

NOAA 1991-2020 normals for Barnes Stn, 24.5 km from Crook County, elevation 3970 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Barnes Stn. 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 2 and the first fall freeze around September 17, a growing season of about 104 days.

Median at 32°F
last June 2, first September 17
Median at 28°F
last May 12, first September 30

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 25Jun 17Jun 12Jun 7Jun 2May 29May 24May 19May 13
28°FJun 1May 26May 20May 16May 12May 7May 4Apr 30Apr 26
24°FMay 14May 8May 4May 1Apr 28Apr 24Apr 20Apr 16Apr 9
20°FApr 30Apr 23Apr 17Apr 12Apr 7Apr 1Mar 27Mar 18Mar 6
16°FApr 4Mar 26Mar 13Mar 7Mar 1Feb 25Feb 19Feb 13Feb 4

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 30Sep 5Sep 9Sep 14Sep 17Sep 20Sep 23Sep 27Oct 1
28°FSep 14Sep 20Sep 24Sep 27Sep 30Oct 3Oct 6Oct 9Oct 16
24°FSep 28Oct 2Oct 6Oct 9Oct 13Oct 16Oct 21Oct 25Nov 2
20°FOct 9Oct 16Oct 21Oct 25Oct 29Nov 1Nov 5Nov 11Nov 19
16°FOct 21Oct 27Nov 1Nov 6Nov 10Nov 16Nov 21Nov 25Dec 3

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°F958681767165605343
32°F13012111411010499938576
28°F163155150145140135129123114
24°F194186180175170165160153145
20°F240226217210202195189182172
16°F285274268259249243234226212

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
6,248
Cooling degree days, base 65°F
388
Growing degree days, base 40°F
4,174
Growing degree days, base 45°F
3,035
Growing degree days, base 50°F
2,108
Growing degree days, base 55°F
1,370
Growing degree days, base 60°F
798

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,01200
February82201
March73507
April574037
May3517167
June16541332
July34169600
August41136560
September17534318
October492182
November79906
December1,04600

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 24.5 km from Crook County. 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 USC00350501 (Barnes Stn). Public domain.