Sherman climate

Sherman Frost Dates and Growing Season

NOAA 1991-2020 normals for Millinocket, 33.1 km from Sherman, elevation 360 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Millinocket. 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 9 and the first fall freeze around October 5, a growing season of about 147 days.

Median at 36°F
last May 22, first September 25
Median at 32°F
last May 9, first October 5
Median at 28°F
last April 29, first October 19

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

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°F142137132129125122118114108
32°F166159154151147144139135128
28°F191184179175171167163158152
24°F214208204200195192188183176
20°F232226222218215211208203197
16°F251243239235232229225221215

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
8,503
Cooling degree days, base 65°F
286
Growing degree days, base 40°F
3,652
Growing degree days, base 45°F
2,716
Growing degree days, base 50°F
1,908
Growing degree days, base 55°F
1,223
Growing degree days, base 60°F
671

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,57800
February1,36500
March1,20000
April758011
May3926136
June12548375
July27116553
August4692511
September21723270
October589048
November90504
December1,30200

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 33.1 km from Sherman. 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 USC00175304 (Millinocket). Public domain.