Carnegie climate

Carnegie Frost Dates and Growing Season

NOAA 1991-2020 normals for Carnegie 5 Ne, 8.3 km from Carnegie, elevation 1481 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Carnegie 5 Ne. 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 16, first October 23
Median at 32°F
last April 6, first October 31
Median at 28°F
last March 25, first November 9

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°FApr 30Apr 26Apr 22Apr 19Apr 16Apr 13Apr 10Apr 6Apr 2
32°FApr 22Apr 18Apr 12Apr 9Apr 6Apr 3Mar 31Mar 26Mar 20
28°FApr 11Apr 6Apr 2Mar 29Mar 25Mar 21Mar 16Mar 11Mar 4
24°FMar 31Mar 24Mar 18Mar 14Mar 10Mar 6Mar 3Feb 28Feb 22
20°FMar 16Mar 11Mar 5Mar 2Feb 28Feb 24Feb 20Feb 15Feb 4
16°FMar 7Mar 1Feb 25Feb 20Feb 15Feb 10Feb 3Jan 28Jan 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°FOct 9Oct 15Oct 18Oct 20Oct 23Oct 25Oct 28Oct 31Nov 4
32°FOct 15Oct 21Oct 25Oct 28Oct 31Nov 3Nov 5Nov 9Nov 14
28°FOct 24Oct 31Nov 3Nov 6Nov 9Nov 12Nov 15Nov 20Nov 26
24°FNov 1Nov 6Nov 11Nov 15Nov 20Nov 24Nov 27Dec 1Dec 7
20°FNov 9Nov 18Nov 24Nov 27Dec 1Dec 4Dec 10Dec 15Dec 21
16°FNov 23Nov 30Dec 4Dec 10Dec 15Dec 19Dec 25Jan 2Jan 12

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°F208201196192188184180176170
32°F230221215211206202197192183
28°F253245239234229224218212203
24°F278271265260255249243236226
20°F308298291284279273267260251
16°F338326318311305299292284270

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
98% 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
3,603
Cooling degree days, base 65°F
2,048
Growing degree days, base 40°F
7,961
Growing degree days, base 45°F
6,478
Growing degree days, base 50°F
5,148
Growing degree days, base 55°F
3,970
Growing degree days, base 60°F
2,939

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January820012
February641028
March4638128
April20237304
May40179605
June1409858
July05491,014
August0518982
September17285718
October16457373
November4736110
December783017

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 8.3 km from Carnegie. 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 USC00341504 (Carnegie 5 Ne). Public domain.