Frost Dates for 01949 — Middleton, Massachusetts

Half of springs at Middleton, MA see their last 32°F night by May 3; only one in ten is past it by April 20, and one in ten still has one after May 20. Planting tender crops after May 9 leaves a 30% risk of a frost on them, after May 14 20%, and after May 20 10%. The 17 days between the even-odds date and the one-in-ten date is wider than at 96% of the 71 Massachusetts stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 9 in half of years, as early as September 29 one year in ten, and holds off past October 24 one year in ten. A hard freeze of 28°F follows 12 days later, around October 21; in spring the one-in-ten date for 28°F is May 6, 14 days before the 32°F one. The freeze-free season lasts 157 days in a typical year, shorter than at 85% of the 71 Massachusetts stations; it reaches 177 days one year in ten and falls short of 138 one year in ten. On average 129 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 14 days longer, to about May 17, and return around October 1. Severe cold of 16°F or below comes every winter, usually between November 30 and March 18.

July is the warmest month at Middleton, MA, averaging 81°F by day and 61°F at night; January is the coldest at 35°F and 16°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 60% of years.

Warmth for growing adds up to 2,473 growing degree days a year (base 50°F), fewer than at 76% of the 71 Massachusetts stations. 29% of them (726) have built up by the end of June, and July adds the most, 639. Precipitation totals 48.2 inches a year, most in October (4.8") and least in February (3.3"); May to September bring 39% of it.

The nearest other station, Beverly Municipal Airport, MA, 5 miles east of Middleton, has a last frost 9 days earlier (April 24), a first frost 8 days later (October 17), a season 20 days longer.

The first measurable snow (0.1 inch or more) in Middleton usually arrives around December 4, and the last of the season around March 23. Those are the middle dates across the winters of 1991–2020 at Middleton, MA, 0.7 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 41 days after the last snow.

ZIP 01949 is under a mile from Middleton, MA, which stands at 110 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 01864 (North Reading). The 2023 USDA Plant Hardiness Zone Map lists ZIP 01949 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.