Barre climate

Barre Frost Dates and Growing Season

NOAA 1991-2020 normals for Barre Falls Dam, 6.4 km from Barre, elevation 825 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Barre Falls Dam. 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 12 and the first fall freeze around October 1, a growing season of about 141 days.

Median at 36°F
last May 25, first September 22
Median at 32°F
last May 12, first October 1
Median at 28°F
last April 29, first October 10

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

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 6Sep 12Sep 16Sep 19Sep 22Sep 24Sep 28Oct 1Oct 4
32°FSep 18Sep 23Sep 27Sep 30Oct 1Oct 3Oct 5Oct 8Oct 15
28°FSep 30Oct 2Oct 5Oct 7Oct 10Oct 14Oct 18Oct 23Oct 29
24°FOct 6Oct 11Oct 16Oct 20Oct 25Oct 29Nov 1Nov 4Nov 10
20°FOct 18Oct 25Oct 30Nov 2Nov 5Nov 9Nov 13Nov 17Nov 23
16°FNov 1Nov 7Nov 12Nov 16Nov 20Nov 24Nov 27Dec 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°F13813212612211811511010597
32°F161154150145141137133127120
28°F188181175170165161156151143
24°F211205200195191185181176169
20°F237231225219215210206201194
16°F263255248243239235229224216

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
6,919
Cooling degree days, base 65°F
482
Growing degree days, base 40°F
4,364
Growing degree days, base 45°F
3,297
Growing degree days, base 50°F
2,380
Growing degree days, base 55°F
1,601
Growing degree days, base 60°F
964

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,28200
February1,10201
March97006
April586253
May28822226
June8389458
July17185634
August36132561
September16748340
October501488
November791013
December1,09701

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 6.4 km from Barre. 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 USC00190408 (Barre Falls Dam). Public domain.