Gardner climate

Gardner Frost Dates and Growing Season

NOAA 1991-2020 normals for Dwight, 12.2 km from Gardner, elevation 628 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Dwight. 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 27 and the first fall freeze around October 15, a growing season of about 170 days.

Median at 36°F
last May 7, first October 3
Median at 32°F
last April 27, first October 15
Median at 28°F
last April 17, first October 25

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 26May 20May 15May 11May 7May 4May 1Apr 29Apr 23
32°FMay 14May 8May 3Apr 30Apr 27Apr 24Apr 21Apr 18Apr 14
28°FMay 2Apr 27Apr 22Apr 20Apr 17Apr 14Apr 11Apr 7Apr 3
24°FApr 21Apr 16Apr 11Apr 8Apr 5Apr 3Apr 1Mar 28Mar 20
20°FApr 10Apr 4Apr 1Mar 30Mar 26Mar 22Mar 18Mar 14Mar 8
16°FMar 31Mar 27Mar 23Mar 19Mar 15Mar 12Mar 8Mar 4Feb 28

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

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°F169163158153149146141135126
32°F188182177173170165160155148
28°F211205199195192188183178170
24°F235227222218214210205200193
20°F257250244238234230225220213
16°F278270264259255249245239232

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
6,462
Cooling degree days, base 65°F
784
Growing degree days, base 40°F
5,160
Growing degree days, base 45°F
4,038
Growing degree days, base 50°F
3,037
Growing degree days, base 55°F
2,152
Growing degree days, base 60°F
1,399

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,32201
February1,08802
March866125
April4895102
May19562346
June31184603
July6248707
August14189640
September10884430
October41011155
November782025
December1,15202

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 12.2 km from Gardner. 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 USC00112500 (Dwight). Public domain.