Frost Dates for 01810 — Andover, Massachusetts

Half of springs at Lawrence, MA see their last 32°F night by April 13; only one in ten is past it by April 1, and one in ten still has one after April 29. Planting tender crops after April 19 leaves a 30% risk of a frost on them, after April 23 20%, and after April 29 10%. The 16 days between the even-odds date and the one-in-ten date is wider than at 87% of the 71 Massachusetts stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 28 in half of years, as early as October 13 one year in ten, and holds off past November 10 one year in ten. A hard freeze of 28°F follows 12 days later, around November 9; in spring the one-in-ten date for 28°F is April 17, 12 days before the 32°F one. The freeze-free season lasts 198 days in a typical year, longer than at 86% of the 71 Massachusetts stations; it reaches 218 days one year in ten and falls short of 176 one year in ten. On average 124 nights a year drop to 32°F or below. Nights of 36°F, when frost can still settle on leaves in low, open spots, continue 12 days longer, to about April 25, and return around October 16. Severe cold of 16°F or below comes every winter, usually between December 12 and March 6.

July is the warmest month at Lawrence, MA, averaging 83°F by day and 65°F at night; January is the coldest at 35°F and 20°F. A freezing night is all but certain in every month from November to March (a 90% chance or more). From May to September the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 90% of years.

Warmth for growing adds up to 3,006 growing degree days a year (base 50°F), more than at 89% of the 71 Massachusetts stations. 31% of them (928) have built up by the end of June, and July adds the most, 739. Precipitation totals 49.4 inches a year, most in March (4.7") and least in July (3.7"); May to September bring 39% of it.

The nearest other station, Lawrence Municipal Airport, MA, 5 miles north of Andover, has a last frost 8 days later (April 21), a first frost 7 days earlier (October 21), a season 16 days shorter.

The first measurable snow (0.1 inch or more) in Andover usually arrives around December 6, and the last of the season around March 24. Those are the middle dates across the winters of 1991–2020 at Lawrence, MA, 3.7 miles away: half of years saw snow earlier, half later. Every one of those winters saw snow. The last 32°F night of spring typically comes 20 days after the last snow.

ZIP 01810 is 4 miles from Lawrence, MA, which stands at 50 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 5 other ZIP codes share the station; its figures are presented in full for 01844 (Methuen). The 2023 USDA Plant Hardiness Zone Map lists ZIP 01810 in zone 6b, the band where the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°C) over 1991–2020; a zone describes winter lows, not frost dates.