Linneus climate

Linneus Frost Dates and Growing Season

NOAA 1991-2020 normals for Houlton Intl AP, 16 km from Linneus, elevation 476 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Houlton Intl 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 27 and the first fall freeze around September 18, a growing season of about 115 days.

Median at 36°F
last June 10, first September 7
Median at 32°F
last May 27, first September 18
Median at 28°F
last May 10, first October 1

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

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°F10810196928984797364
32°F13512812411911511010610194
28°F162154150147143139134129121
24°F190182177172168164159153147
20°F214207203198195190186181174
16°F234227222218214211206202195

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
9,034
Cooling degree days, base 65°F
207
Growing degree days, base 40°F
3,309
Growing degree days, base 45°F
2,404
Growing degree days, base 50°F
1,636
Growing degree days, base 55°F
1,001
Growing degree days, base 60°F
517

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,61500
February1,40700
March1,22501
April79209
May4325112
June17735311
July5488499
August8162447
September28317214
October644138
November95904
December1,36700

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 16 km from Linneus. 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 USW00014609 (Houlton Intl AP). Public domain.