Brownfield climate

Brownfield Frost Dates and Growing Season

NOAA 1991-2020 normals for Fryeburg E Slopes AP, 6.6 km from Brownfield, elevation 445 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Fryeburg E Slopes AP. 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 17 and the first fall freeze around September 25, a growing season of about 128 days.

Median at 36°F
last May 29, first September 13
Median at 32°F
last May 17, first September 25
Median at 28°F
last May 4, first October 4

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 12Jun 8Jun 4Jun 1May 29May 26May 22May 19May 16
32°FJun 1May 26May 22May 19May 17May 14May 11May 7May 2
28°FMay 18May 13May 8May 6May 4May 1Apr 30Apr 27Apr 23
24°FMay 3Apr 30Apr 27Apr 24Apr 22Apr 20Apr 17Apr 14Apr 10
20°FApr 22Apr 18Apr 16Apr 13Apr 10Apr 8Apr 6Apr 3Apr 1
16°FApr 15Apr 10Apr 6Apr 4Apr 2Apr 1Mar 29Mar 25Mar 21

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 5Sep 8Sep 11Sep 13Sep 16Sep 19Sep 23Sep 28
32°FSep 11Sep 15Sep 18Sep 21Sep 25Sep 27Sep 30Oct 3Oct 7
28°FSep 20Sep 26Sep 29Oct 1Oct 4Oct 6Oct 10Oct 14Oct 20
24°FOct 1Oct 6Oct 9Oct 14Oct 17Oct 20Oct 24Oct 30Nov 3
20°FOct 13Oct 19Oct 24Oct 28Nov 1Nov 3Nov 5Nov 10Nov 15
16°FOct 28Nov 1Nov 5Nov 9Nov 12Nov 15Nov 18Nov 21Nov 25

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°F1271201161121081041019589
32°F147142136132128125121116109
28°F171164158154151147144139133
24°F198190185180176172168164157
20°F221214208205201197193188181
16°F240233229225222218214210202

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
7,734
Cooling degree days, base 65°F
373
Growing degree days, base 40°F
3,995
Growing degree days, base 45°F
2,997
Growing degree days, base 50°F
2,133
Growing degree days, base 55°F
1,399
Growing degree days, base 60°F
803

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,43500
February1,22400
March1,06804
April666133
May32413189
June10068420
July22149592
August38109536
September20632289
October550164
November86907
December1,23400

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 6.6 km from Brownfield. 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 USW00054772 (Fryeburg E Slopes AP). Public domain.