Daggett County climate

Daggett County Frost Dates and Growing Season

NOAA 1991-2020 normals for Flaming Gorge, 9.5 km from Daggett County, elevation 6244 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Flaming Gorge. 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 26 and the first fall freeze around September 23, a growing season of about 120 days.

Median at 36°F
last June 9, first September 14
Median at 32°F
last May 26, first September 23
Median at 28°F
last May 10, first October 3

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 25Jun 20Jun 16Jun 12Jun 9Jun 7Jun 3May 31May 26
32°FJun 10Jun 5Jun 2May 29May 26May 22May 19May 15May 9
28°FMay 29May 22May 17May 13May 10May 6May 3Apr 30Apr 26
24°FMay 14May 7May 3Apr 30Apr 28Apr 24Apr 20Apr 16Apr 11
20°FMay 3Apr 27Apr 21Apr 17Apr 13Apr 10Apr 7Apr 3Mar 28
16°FApr 17Apr 11Apr 7Apr 3Mar 31Mar 27Mar 22Mar 16Mar 11

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 1Sep 5Sep 8Sep 11Sep 14Sep 16Sep 19Sep 22Sep 26
32°FSep 9Sep 13Sep 17Sep 20Sep 23Sep 25Sep 28Oct 1Oct 4
28°FSep 19Sep 24Sep 28Oct 1Oct 3Oct 5Oct 9Oct 13Oct 18
24°FSep 29Oct 3Oct 7Oct 11Oct 14Oct 18Oct 21Oct 24Oct 28
20°FOct 8Oct 14Oct 18Oct 21Oct 25Oct 28Oct 30Nov 3Nov 7
16°FOct 16Oct 22Oct 27Oct 30Nov 2Nov 5Nov 8Nov 12Nov 16

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°F114108103999592878275
32°F13913312812412011511110598
28°F165158153149144140136131122
24°F190183178174170165160154147
20°F215208203197192188182177168
16°F239231226220215210205199189

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
7,300
Cooling degree days, base 65°F
346
Growing degree days, base 40°F
3,931
Growing degree days, base 45°F
2,910
Growing degree days, base 50°F
2,051
Growing degree days, base 55°F
1,339
Growing degree days, base 60°F
768

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,24600
February1,05100
March87404
April643023
May3883139
June12445374
July18160608
August27121560
September19717286
October566055
November92303
December1,24300

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 9.5 km from Daggett 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 USC00422864 (Flaming Gorge). Public domain.