Frost Dates for 01060 — Northampton, Massachusetts

Half of springs at Amherst, MA see their last 32°F night by May 5; only one in ten is past it by April 23, and one in ten still has one after May 19. Planting tender crops after May 11 leaves a 30% risk of a frost on them, after May 15 20%, and after May 19 10%. The 14 days between the even-odds date and the one-in-ten date is wider than at 51% of the 71 Massachusetts stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 8 in half of years, as early as September 28 one year in ten, and holds off past October 23 one year in ten. A hard freeze of 28°F follows 13 days later, around October 21; in spring the one-in-ten date for 28°F is May 7, 12 days before the 32°F one. The freeze-free season lasts 156 days in a typical year, shorter than at 87% of the 71 Massachusetts stations; it reaches 175 days one year in ten and falls short of 137 one year in ten. On average 153 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 May 17, and return around September 30. Severe cold of 16°F or below comes every winter, usually between November 26 and March 18.

July is the warmest month at Amherst, MA, averaging 83°F by day and 60°F at night; January is the coldest at 34°F and 14°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 67% of years.

Warmth for growing adds up to 2,598 growing degree days a year (base 50°F), fewer than at 58% of the 71 Massachusetts stations. 31% of them (812) have built up by the end of June, and July adds the most, 671. Precipitation totals 46.6 inches a year, most in October (4.7") and least in February (2.9"); May to September bring 45% of it.

The nearest other station, Leverett #2, MA, 10 miles northeast of Northampton and 170 feet higher, has a last frost 3 days earlier (May 2), a first frost 1 day later (October 9), a season 4 days longer.

The first measurable snow (0.1 inch or more) in Northampton usually arrives around November 28, and the last of the season around March 25. Those are the middle dates across the winters of 1991–2020 at Amherst, MA, 6.6 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 01060 is 7 miles from Amherst, MA, which stands at 145 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 01002 (Amherst). The 2023 USDA Plant Hardiness Zone Map lists ZIP 01060 in zone 6a, the band where the coldest night of the year averaged -10 to -5°F (-23.3 to -20.6°C) over 1991–2020; a zone describes winter lows, not frost dates.