Crawford climate

Crawford Frost Dates and Growing Season

NOAA 1991-2020 normals for Ft Robinson, 4.4 km from Crawford, elevation 3812 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Ft Robinson. 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 13 and the first fall freeze around September 30, a growing season of about 138 days.

Median at 36°F
last May 29, first September 22
Median at 32°F
last May 13, first September 30
Median at 28°F
last May 1, first October 9

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 15Jun 9Jun 5Jun 1May 29May 25May 22May 18May 12
32°FJun 2May 28May 23May 17May 13May 10May 7May 4Apr 30
28°FMay 14May 9May 5May 3May 1Apr 29Apr 26Apr 22Apr 16
24°FMay 4Apr 30Apr 27Apr 23Apr 20Apr 17Apr 14Apr 10Apr 5
20°FApr 26Apr 21Apr 16Apr 12Apr 9Apr 5Apr 2Mar 30Mar 23
16°FApr 17Apr 11Apr 6Apr 3Mar 31Mar 28Mar 23Mar 19Mar 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°FSep 6Sep 11Sep 15Sep 19Sep 22Sep 24Sep 27Sep 30Oct 3
32°FSep 15Sep 21Sep 25Sep 28Sep 30Oct 2Oct 4Oct 8Oct 13
28°FSep 24Sep 30Oct 4Oct 6Oct 9Oct 12Oct 15Oct 18Oct 21
24°FOct 5Oct 10Oct 13Oct 16Oct 19Oct 21Oct 23Oct 26Oct 30
20°FOct 13Oct 18Oct 21Oct 23Oct 26Oct 28Oct 31Nov 2Nov 7
16°FOct 20Oct 24Oct 28Oct 30Nov 2Nov 5Nov 8Nov 12Nov 17

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°F1361301241201151101049991
32°F159152147143138134129122115
28°F178172168164160156152147140
24°F200193187183179175171167160
20°F219212208203199195190185177
16°F240231225220216211207201194

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
6,887
Cooling degree days, base 65°F
726
Growing degree days, base 40°F
4,644
Growing degree days, base 45°F
3,568
Growing degree days, base 50°F
2,654
Growing degree days, base 55°F
1,882
Growing degree days, base 60°F
1,238

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,19700
February1,03302
March847016
April585150
May31519217
June8298469
July9278734
August19255701
September15473382
October558477
November89607
December1,19300

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 4.4 km from Crawford. 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 USC00253015 (Ft Robinson). Public domain.