Frost Dates for 02322 — Avon, Massachusetts

Half of springs at Brockton, MA see their last 32°F night by April 22; only one in ten is past it by April 8, and one in ten still has one after May 5. Planting tender crops after April 28 leaves a 30% risk of a frost on them, after May 1 20%, and after May 5 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 51% of the 71 Massachusetts stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 19 in half of years, as early as October 5 one year in ten, and holds off past November 3 one year in ten. A hard freeze of 28°F follows 12 days later, around October 31; in spring the one-in-ten date for 28°F is April 20, 15 days before the 32°F one. The freeze-free season lasts 178 days in a typical year, longer than at 69% of the 71 Massachusetts stations; it reaches 198 days one year in ten and falls short of 158 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 13 days longer, to about May 5, and return around October 7. Severe cold of 16°F or below comes every winter, usually between December 9 and March 8.

July is the warmest month at Brockton, MA, averaging 84°F by day and 63°F at night; January is the coldest at 39°F and 21°F. A freezing night is all but certain in every month from November to April (a 90% chance or more). From June to September the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 22% of years.

Warmth for growing adds up to 2,982 growing degree days a year (base 50°F), more than at 87% of the 71 Massachusetts stations. 30% of them (899) have built up by the end of June, and July adds the most, 738. Precipitation totals 50.2 inches a year, most in March (5.2") and least in July (3.2"); May to September bring 37% of it.

The nearest other station, Blue Hill Coop, MA, 7 miles northwest of Avon and 550 feet higher, has a last frost 4 days earlier (April 18), a first frost 7 days later (October 26), a season 12 days longer.

The first measurable snow (0.1 inch or more) in Avon usually arrives around December 20, and the last of the season around March 14. Those are the middle dates across the winters of 1991–2020 at Brockton, MA, 5.5 miles away: half of years saw snow earlier, half later. Snow fell in 89% of those winters. The last 32°F night of spring typically comes 39 days after the last snow.

ZIP 02322 is 6 miles from Brockton, MA, which stands at 75 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 7 other ZIP codes share the station; its figures are presented in full for 02301 (Brockton). The 2023 USDA Plant Hardiness Zone Map lists ZIP 02322 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.