Greenwood climate

Greenwood Frost Dates and Growing Season

NOAA 1991-2020 normals for Bethel 6 Sse, 8.4 km from Greenwood, elevation 790 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Bethel 6 Sse. 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 6 and the first fall freeze around October 2, a growing season of about 147 days.

Median at 36°F
last May 19, first September 22
Median at 32°F
last May 6, first October 2
Median at 28°F
last April 25, first October 17

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 1May 27May 23May 21May 19May 16May 14May 11May 7
32°FMay 19May 14May 11May 8May 6May 4May 2Apr 30Apr 27
28°FMay 5May 1Apr 30Apr 27Apr 25Apr 23Apr 21Apr 18Apr 13
24°FApr 23Apr 20Apr 18Apr 16Apr 13Apr 10Apr 8Apr 5Apr 2
20°FApr 15Apr 11Apr 8Apr 6Apr 4Apr 2Apr 1Mar 29Mar 24
16°FApr 6Apr 4Apr 1Mar 31Mar 28Mar 25Mar 22Mar 19Mar 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 10Sep 14Sep 17Sep 20Sep 22Sep 25Sep 27Oct 1Oct 5
32°FSep 20Sep 24Sep 27Oct 1Oct 2Oct 5Oct 8Oct 13Oct 19
28°FOct 1Oct 4Oct 9Oct 13Oct 17Oct 21Oct 25Oct 29Nov 3
24°FOct 15Oct 21Oct 25Oct 29Nov 1Nov 3Nov 7Nov 11Nov 16
20°FOct 31Nov 4Nov 7Nov 11Nov 14Nov 16Nov 19Nov 22Nov 27
16°FNov 11Nov 15Nov 18Nov 21Nov 23Nov 26Nov 29Dec 1Dec 6

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°F143137132129125122118113108
32°F167160155151147144140135128
28°F196189184179175170165161155
24°F220213209205201197193189183
20°F240234230226223220216212205
16°F259251247243240236233228223

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
7,930
Cooling degree days, base 65°F
287
Growing degree days, base 40°F
3,798
Growing degree days, base 45°F
2,822
Growing degree days, base 50°F
1,978
Growing degree days, base 55°F
1,271
Growing degree days, base 60°F
699

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,46100
February1,24000
March1,11105
April702022
May3569160
June12050384
July24114555
August3283516
September21930276
October564154
November87006
December1,23100

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 8.4 km from Greenwood. 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 USC00170583 (Bethel 6 Sse). Public domain.