Somers climate

Somers Frost Dates and Growing Season

NOAA 1991-2020 normals for Staffordville, 15.4 km from Somers, elevation 736 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Staffordville. 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 7 and the first fall freeze around October 12, a growing season of about 159 days.

Median at 36°F
last May 19, first October 3
Median at 32°F
last May 7, first October 12
Median at 28°F
last April 25, first October 24

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

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°F156149145141138135131127121
32°F178171167163159155151146140
28°F204197192187182178173168162
24°F229221217212209204200195186
20°F253246241236233229224219212
16°F272266260256251248244239232

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
6,894
Cooling degree days, base 65°F
405
Growing degree days, base 40°F
4,309
Growing degree days, base 45°F
3,233
Growing degree days, base 50°F
2,310
Growing degree days, base 55°F
1,527
Growing degree days, base 60°F
886

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,28200
February1,10601
March98606
April612139
May3159192
June8763428
July14159611
August22127570
September14142354
October475393
November767015
December1,08801

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 15.4 km from Somers. 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 USC00067958 (Staffordville). Public domain.