Sugar Grove climate

Sugar Grove Frost Dates and Growing Season

NOAA 1991-2020 normals for Chandlers Valley 1SE, 6.8 km from Sugar Grove, elevation 1490 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Chandlers Valley 1SE. 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 22 and the first fall freeze around September 30, a growing season of about 131 days.

Median at 36°F
last June 3, first September 18
Median at 32°F
last May 22, first September 30
Median at 28°F
last May 8, 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 20Jun 14Jun 10Jun 6Jun 3Jun 1May 30May 26May 21
32°FJun 5May 31May 28May 26May 22May 19May 15May 10May 6
28°FMay 25May 19May 14May 11May 8May 4Apr 30Apr 28Apr 24
24°FMay 14May 8May 3Apr 30Apr 27Apr 23Apr 21Apr 18Apr 13
20°FApr 26Apr 21Apr 18Apr 15Apr 12Apr 9Apr 6Apr 3Mar 31
16°FApr 15Apr 9Apr 5Apr 3Apr 1Mar 31Mar 27Mar 23Mar 18

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

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°F126119114109104100958980
32°F152145140135131127123117109
28°F180172165161156152147142135
24°F204197192187183178173167158
20°F232226220216212208203197189
16°F257249243238234229225220213

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
7,504
Cooling degree days, base 65°F
274
Growing degree days, base 40°F
3,913
Growing degree days, base 45°F
2,887
Growing degree days, base 50°F
2,004
Growing degree days, base 55°F
1,259
Growing degree days, base 60°F
674

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,33401
February1,17901
March1,04509
April651041
May34713189
June11354394
July45101521
August6276479
September20427282
October536379
November83907
December1,15001

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 6.8 km from Sugar Grove. 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 USC00361362 (Chandlers Valley 1SE). Public domain.