North Andover climate

North Andover Frost Dates and Growing Season

NOAA 1991-2020 normals for Lawrence Muni AP, 2.2 km from North Andover, elevation 149 ft

Frost and the growing season

NOAA's 1991-2020 freeze probabilities for Lawrence Muni 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 April 21 and the first fall freeze around October 21, a growing season of about 182 days.

Median at 36°F
last May 3, first October 9
Median at 32°F
last April 21, first October 21
Median at 28°F
last April 7, first November 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°FMay 16May 11May 7May 5May 3Apr 30Apr 28Apr 25Apr 23
32°FMay 1Apr 28Apr 25Apr 23Apr 21Apr 19Apr 16Apr 13Apr 9
28°FApr 20Apr 16Apr 13Apr 10Apr 7Apr 5Apr 3Apr 1Mar 29
24°FApr 7Apr 4Apr 2Mar 31Mar 29Mar 25Mar 22Mar 17Mar 13
20°FApr 1Mar 29Mar 25Mar 21Mar 18Mar 15Mar 12Mar 10Mar 5
16°FMar 25Mar 19Mar 15Mar 13Mar 11Mar 8Mar 5Mar 1Feb 24

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 29Oct 1Oct 4Oct 6Oct 9Oct 11Oct 15Oct 18Oct 23
32°FOct 6Oct 10Oct 14Oct 18Oct 21Oct 24Oct 27Oct 31Nov 5
28°FOct 19Oct 24Oct 27Oct 30Nov 1Nov 4Nov 8Nov 11Nov 16
24°FNov 1Nov 4Nov 8Nov 11Nov 15Nov 18Nov 22Nov 26Dec 1
20°FNov 14Nov 18Nov 22Nov 26Nov 29Dec 1Dec 4Dec 10Dec 16
16°FNov 27Dec 1Dec 4Dec 7Dec 11Dec 15Dec 18Dec 22Dec 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°F174169164161157154150145139
32°F202195190186182179175170163
28°F226220215211208204201197190
24°F253246241237233229224219212
20°F275268263258254250246242233
16°F296289284279275271267261254

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
6,095
Cooling degree days, base 65°F
710
Growing degree days, base 40°F
5,003
Growing degree days, base 45°F
3,846
Growing degree days, base 50°F
2,840
Growing degree days, base 55°F
1,983
Growing degree days, base 60°F
1,274

Growing degree days by month, base 50°F

Heating and cooling by month

MonthHeating DDCooling DDGrowing DD 50
January1,17601
February1,00701
March878114
April525571
May24328263
June55121517
July5259719
August10216671
September10874417
October4027135
November683028
December1,00303

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 2.2 km from North Andover. 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 USW00094723 (Lawrence Muni AP). Public domain.