Copeland climate

Copeland Frost Dates and Growing Season

NOAA 1991-2020 normals for Anderson 3W, 30.6 km from Copeland, elevation 1117 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Anderson 3W. 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 15 and the first fall freeze around October 26, a growing season of about 194 days.

Median at 36°F
last April 27, first October 18
Median at 32°F
last April 15, first October 26
Median at 28°F
last April 4, first November 4

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 10May 5May 1Apr 30Apr 27Apr 23Apr 19Apr 16Apr 11
32°FApr 30Apr 25Apr 21Apr 18Apr 15Apr 12Apr 9Apr 5Mar 31
28°FApr 19Apr 13Apr 10Apr 7Apr 4Apr 1Mar 28Mar 23Mar 15
24°FApr 8Apr 3Mar 31Mar 27Mar 22Mar 17Mar 13Mar 9Mar 4
20°FMar 30Mar 20Mar 16Mar 12Mar 8Mar 5Mar 2Feb 27Feb 21
16°FMar 15Mar 10Mar 6Mar 2Feb 28Feb 24Feb 19Feb 14Feb 6

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 4Oct 8Oct 12Oct 15Oct 18Oct 20Oct 22Oct 25Oct 29
32°FOct 14Oct 18Oct 21Oct 23Oct 26Oct 28Oct 31Nov 3Nov 8
28°FOct 22Oct 27Oct 31Nov 2Nov 4Nov 7Nov 10Nov 14Nov 19
24°FOct 31Nov 3Nov 7Nov 10Nov 14Nov 17Nov 21Nov 25Dec 1
20°FNov 7Nov 13Nov 17Nov 21Nov 25Nov 29Dec 2Dec 7Dec 13
16°FNov 17Nov 23Nov 27Dec 1Dec 4Dec 9Dec 14Dec 22Dec 30

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°F194187181178174170166161156
32°F215207202198194190186181174
28°F238231224219214210206201193
24°F262254248242238232227221214
20°F286277271266260255250243236
16°F313302295288283277272265257

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
4,256
Cooling degree days, base 65°F
1,451
Growing degree days, base 40°F
6,943
Growing degree days, base 45°F
5,544
Growing degree days, base 50°F
4,293
Growing degree days, base 55°F
3,198
Growing degree days, base 60°F
2,250

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January94208
February734030
March548591
April27819235
May10397463
June6269714
July1424888
August1401865
September34191608
October23941294
November532482
December839016

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 30.6 km from Copeland. 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 USC00230163 (Anderson 3W). Public domain.