Mancos climate

Mancos Frost Dates and Growing Season

NOAA 1991-2020 normals for Mancos 1SW, 2.6 km from Mancos, elevation 6897 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Mancos 1SW. 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 4 and the first fall freeze around September 24, a growing season of about 111 days.

Median at 36°F
last June 15, first September 15
Median at 32°F
last June 4, first September 24
Median at 28°F
last May 21, first October 2

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

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 3Sep 6Sep 9Sep 12Sep 15Sep 18Sep 21Sep 24Sep 27
32°FSep 9Sep 13Sep 18Sep 21Sep 24Sep 26Sep 29Oct 1Oct 4
28°FSep 17Sep 23Sep 27Sep 30Oct 2Oct 4Oct 6Oct 10Oct 15
24°FSep 26Oct 1Oct 4Oct 7Oct 10Oct 13Oct 17Oct 21Oct 26
20°FOct 5Oct 10Oct 14Oct 18Oct 21Oct 24Oct 28Nov 1Nov 5
16°FOct 16Oct 21Oct 25Oct 29Nov 1Nov 4Nov 7Nov 12Nov 18

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°F10910399949086817669
32°F1281231181141111061029790
28°F153146140135132128124118111
24°F178171165161156152147141134
20°F203195189184179175169164157
16°F233223216211206201195189181

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
6,978
Cooling degree days, base 65°F
190
Growing degree days, base 40°F
3,778
Growing degree days, base 45°F
2,728
Growing degree days, base 50°F
1,851
Growing degree days, base 55°F
1,136
Growing degree days, base 60°F
575

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,20300
February97000
March84301
April621019
May3921127
June12226356
July1398550
August3359491
September2055260
October544046
November86301
December1,17000

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 2.6 km from Mancos. 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 USC00055327 (Mancos 1SW). Public domain.