New Limerick climate

New Limerick Frost Dates and Growing Season

NOAA 1991-2020 normals for Houlton 5N, 14.8 km from New Limerick, elevation 390 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Houlton 5N. 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 19 and the first fall freeze around September 23, a growing season of about 125 days.

Median at 36°F
last June 1, first September 10
Median at 32°F
last May 19, first September 23
Median at 28°F
last May 4, first October 5

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 16Jun 10Jun 7Jun 4Jun 1May 30May 27May 24May 20
32°FJun 2May 29May 25May 22May 19May 16May 12May 8May 3
28°FMay 18May 13May 10May 7May 4May 2Apr 30Apr 28Apr 24
24°FMay 7May 2Apr 30Apr 28Apr 25Apr 22Apr 19Apr 15Apr 10
20°FApr 24Apr 20Apr 17Apr 14Apr 11Apr 8Apr 6Apr 4Apr 1
16°FApr 16Apr 11Apr 8Apr 6Apr 4Apr 2Mar 31Mar 29Mar 25

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

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°F11811210810410197938781
32°F146139133129125121117112105
28°F171164159155151147144139131
24°F198191186182177173169163157
20°F222217212209205201197192184
16°F242236231228224221218213207

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
8,667
Cooling degree days, base 65°F
247
Growing degree days, base 40°F
3,547
Growing degree days, base 45°F
2,613
Growing degree days, base 50°F
1,808
Growing degree days, base 55°F
1,134
Growing degree days, base 60°F
606

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,59300
February1,37300
March1,18701
April750012
May3856139
June13543360
July35102532
August5976482
September25019238
October610141
November94104
December1,35000

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 14.8 km from New Limerick. 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 USC00173944 (Houlton 5N). Public domain.