Valier climate

Valier Frost Dates and Growing Season

NOAA 1991-2020 normals for Valier, 0.4 km from Valier, elevation 3807 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Valier. 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 17 and the first fall freeze around September 24, a growing season of about 129 days.

Median at 36°F
last June 2, first September 13
Median at 32°F
last May 17, first September 24
Median at 28°F
last May 4, first October 4

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

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°FAug 29Sep 3Sep 7Sep 10Sep 13Sep 16Sep 19Sep 22Sep 26
32°FSep 11Sep 16Sep 19Sep 22Sep 24Sep 27Sep 29Oct 1Oct 5
28°FSep 22Sep 27Sep 30Oct 1Oct 4Oct 6Oct 9Oct 12Oct 17
24°FOct 1Oct 3Oct 7Oct 10Oct 13Oct 16Oct 20Oct 23Oct 28
20°FOct 6Oct 11Oct 15Oct 18Oct 22Oct 25Oct 29Nov 2Nov 7
16°FOct 13Oct 18Oct 23Oct 27Oct 31Nov 2Nov 5Nov 10Nov 15

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°F12111410910510196928575
32°F147141137133129125121115107
28°F170163159155152148144140133
24°F194186181176172168164159153
20°F216207202198193188183178170
16°F236227220215210205200194185

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
7,823
Cooling degree days, base 65°F
246
Growing degree days, base 40°F
3,608
Growing degree days, base 45°F
2,599
Growing degree days, base 50°F
1,762
Growing degree days, base 55°F
1,092
Growing degree days, base 60°F
587

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,26900
February1,09601
March98304
April671025
May4153125
June19617280
July53110523
August6695497
September25020247
October623157
November96304
December1,24000

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 0.4 km from Valier. 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 USC00248501 (Valier). Public domain.