Greenbush climate

Greenbush Frost Dates and Growing Season

NOAA 1991-2020 normals for Old Town 2 W, 17.3 km from Greenbush, elevation 127 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Old Town 2 W. 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 13 and the first fall freeze around September 28, a growing season of about 137 days.

Median at 36°F
last May 28, first September 18
Median at 32°F
last May 13, first September 28
Median at 28°F
last April 30, first October 11

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 9Jun 5Jun 2May 31May 28May 25May 22May 18May 14
32°FMay 28May 23May 19May 16May 13May 11May 7May 3Apr 30
28°FMay 13May 8May 4May 2Apr 30Apr 28Apr 25Apr 22Apr 19
24°FApr 29Apr 26Apr 23Apr 21Apr 18Apr 15Apr 12Apr 8Apr 4
20°FApr 20Apr 15Apr 12Apr 8Apr 6Apr 4Apr 2Mar 31Mar 26
16°FApr 10Apr 6Apr 3Apr 1Mar 31Mar 28Mar 24Mar 20Mar 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°FSep 5Sep 9Sep 12Sep 15Sep 18Sep 21Sep 24Sep 27Oct 1
32°FSep 16Sep 21Sep 24Sep 26Sep 28Oct 1Oct 4Oct 7Oct 11
28°FSep 27Oct 1Oct 5Oct 8Oct 11Oct 14Oct 17Oct 22Oct 28
24°FOct 9Oct 15Oct 19Oct 24Oct 27Oct 30Nov 2Nov 5Nov 10
20°FOct 26Nov 1Nov 3Nov 6Nov 9Nov 11Nov 14Nov 18Nov 22
16°FNov 6Nov 11Nov 14Nov 17Nov 20Nov 22Nov 25Nov 28Dec 3

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°F13012512111711310910510196
32°F155149145140137134130125117
28°F183174170165161157153149142
24°F210204199194191186182177168
20°F234228223219215211207202196
16°F254249244239236232229224218

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
8,146
Cooling degree days, base 65°F
235
Growing degree days, base 40°F
3,617
Growing degree days, base 45°F
2,643
Growing degree days, base 50°F
1,816
Growing degree days, base 55°F
1,132
Growing degree days, base 60°F
597

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,49600
February1,27500
March1,10502
April714015
May3875128
June14332341
July29106542
August5572482
September23820249
October577151
November87606
December1,25100

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 17.3 km from Greenbush. 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 USW00094644 (Old Town 2 W). Public domain.