Nicholson climate

Nicholson Frost Dates and Growing Season

NOAA 1991-2020 normals for Montrose, 25.9 km from Nicholson, elevation 1420 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Montrose. 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 14 and the first fall freeze around October 2, a growing season of about 141 days.

Median at 36°F
last May 26, first September 23
Median at 32°F
last May 14, first October 2
Median at 28°F
last May 2, first October 15

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 6Jun 2May 31May 28May 26May 23May 20May 15May 9
32°FMay 28May 24May 21May 17May 14May 11May 7May 2Apr 29
28°FMay 20May 15May 10May 6May 2Apr 30Apr 27Apr 24Apr 19
24°FMay 9May 2Apr 28Apr 24Apr 21Apr 18Apr 14Apr 10Apr 6
20°FApr 27Apr 20Apr 15Apr 11Apr 7Apr 5Apr 3Mar 31Mar 26
16°FApr 12Apr 6Apr 4Apr 2Mar 31Mar 28Mar 24Mar 20Mar 15

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 9Sep 14Sep 17Sep 20Sep 23Sep 25Sep 28Oct 1Oct 4
32°FSep 20Sep 25Sep 29Oct 1Oct 2Oct 4Oct 7Oct 10Oct 15
28°FOct 1Oct 4Oct 7Oct 11Oct 15Oct 18Oct 20Oct 24Oct 29
24°FOct 14Oct 20Oct 23Oct 26Oct 29Nov 1Nov 3Nov 7Nov 12
20°FNov 1Nov 3Nov 6Nov 9Nov 12Nov 14Nov 18Nov 21Nov 28
16°FNov 7Nov 12Nov 15Nov 18Nov 22Nov 25Nov 29Dec 3Dec 9

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°F139131126122118115111107101
32°F161154148144141136132128122
28°F184176171166163157153147141
24°F211204199194189184179173166
20°F239231226221217214209204196
16°F261252247242238234229223217

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
7,498
Cooling degree days, base 65°F
313
Growing degree days, base 40°F
3,964
Growing degree days, base 45°F
2,948
Growing degree days, base 50°F
2,067
Growing degree days, base 55°F
1,324
Growing degree days, base 60°F
729

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,33901
February1,17700
March1,05203
April656242
May33315189
June10763409
July33116549
August4894511
September20622280
October540172
November842011
December1,16601

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 25.9 km from Nicholson. 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 USC00365915 (Montrose). Public domain.