Calumet climate

Calumet Frost Dates and Growing Season

NOAA 1991-2020 normals for El Reno 1 N, 15.9 km from Calumet, elevation 1325 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for El Reno 1 N. 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 April 6 and the first fall freeze around October 31, a growing season of about 206 days.

Median at 36°F
last April 17, first October 21
Median at 32°F
last April 6, first October 31
Median at 28°F
last March 26, first November 7

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 1Apr 26Apr 24Apr 21Apr 17Apr 14Apr 10Apr 7Apr 1
32°FApr 22Apr 16Apr 12Apr 9Apr 6Apr 3Mar 31Mar 27Mar 21
28°FApr 11Apr 6Apr 2Mar 30Mar 26Mar 22Mar 18Mar 14Mar 9
24°FApr 1Mar 27Mar 23Mar 18Mar 14Mar 11Mar 8Mar 4Feb 27
20°FMar 20Mar 14Mar 11Mar 7Mar 4Mar 1Feb 26Feb 22Feb 14
16°FMar 13Mar 8Mar 3Feb 28Feb 23Feb 18Feb 12Feb 4Jan 24

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°FOct 3Oct 10Oct 15Oct 18Oct 21Oct 24Oct 27Oct 31Nov 4
32°FOct 15Oct 21Oct 24Oct 28Oct 31Nov 2Nov 5Nov 8Nov 13
28°FOct 24Oct 30Nov 2Nov 5Nov 7Nov 11Nov 14Nov 18Nov 24
24°FOct 31Nov 6Nov 9Nov 13Nov 16Nov 20Nov 24Nov 29Dec 3
20°FNov 8Nov 15Nov 20Nov 24Nov 28Dec 1Dec 5Dec 12Dec 20
16°FNov 19Nov 27Dec 1Dec 6Dec 12Dec 18Dec 24Dec 31Jan 8

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°F205198193189185181177172164
32°F227220215211206202198193185
28°F247240235230226222217211203
24°F271263257252247242237231222
20°F297287280274268263258251242
16°F324312305298292286279271261

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
3,917
Cooling degree days, base 65°F
1,814
Growing degree days, base 40°F
7,514
Growing degree days, base 45°F
6,077
Growing degree days, base 50°F
4,796
Growing degree days, base 55°F
3,662
Growing degree days, base 60°F
2,667

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January87306
February692023
March5106113
April22828274
May56144554
June2353801
July0521986
August1473937
September31234653
October19250344
November516492
December817015

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 15.9 km from Calumet. 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 USC00342818 (El Reno 1 N). Public domain.