Fountain climate

Fountain Frost Dates and Growing Season

NOAA 1991-2020 normals for Colorado Springs Muni AP, 14.3 km from Fountain, elevation 6181 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Colorado Springs Muni AP. 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 3 and the first fall freeze around October 8, a growing season of about 158 days.

Median at 36°F
last May 14, first October 1
Median at 32°F
last May 3, first October 8
Median at 28°F
last April 24, first October 16

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°FMay 26May 22May 18May 16May 14May 12May 9May 7May 3
32°FMay 15May 11May 8May 6May 3May 1Apr 30Apr 27Apr 22
28°FMay 5May 2Apr 30Apr 27Apr 24Apr 21Apr 17Apr 14Apr 8
24°FApr 27Apr 22Apr 19Apr 15Apr 12Apr 8Apr 5Apr 1Mar 27
20°FApr 19Apr 13Apr 7Apr 4Apr 1Mar 29Mar 24Mar 18Mar 11
16°FApr 7Apr 1Mar 27Mar 23Mar 17Mar 13Mar 9Mar 5Feb 27

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 17Sep 23Sep 26Sep 28Oct 1Oct 3Oct 5Oct 8Oct 12
32°FSep 26Oct 1Oct 3Oct 6Oct 8Oct 10Oct 13Oct 16Oct 19
28°FOct 4Oct 8Oct 11Oct 13Oct 16Oct 19Oct 22Oct 25Oct 29
24°FOct 11Oct 17Oct 20Oct 23Oct 26Oct 29Nov 1Nov 4Nov 8
20°FOct 20Oct 25Oct 30Nov 1Nov 4Nov 7Nov 10Nov 14Nov 19
16°FOct 27Nov 2Nov 5Nov 9Nov 14Nov 17Nov 20Nov 24Nov 29

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°F154149145142139136132127120
32°F174168164161158154150147140
28°F193187183179176172168164158
24°F217210205200196191187182175
20°F243235228222217212207201193
16°F264256250245239234228222213

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
5,889
Cooling degree days, base 65°F
608
Growing degree days, base 40°F
4,938
Growing degree days, base 45°F
3,747
Growing degree days, base 50°F
2,730
Growing degree days, base 55°F
1,872
Growing degree days, base 60°F
1,162

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,03101
February88603
March741023
April526173
May26217251
June53119516
July6234693
August14172623
September12262399
October4483127
November767019
December1,03401

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 14.3 km from Fountain. 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 USW00093037 (Colorado Springs Muni AP). Public domain.