Frost Dates for 04276 — Rumford, Maine

Half of springs at Rumford 1 SSE, ME see their last 32°F night by May 4; only one in ten is past it by April 23, and one in ten still has one after May 17. Planting tender crops after May 10 leaves a 30% risk of a frost on them, after May 13 20%, and after May 17 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 33% of the 52 Maine stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 6 in half of years, as early as September 26 one year in ten, and holds off past October 20 one year in ten. A hard freeze of 28°F follows 12 days later, around October 18; in spring the one-in-ten date for 28°F is May 4, 13 days before the 32°F one. The freeze-free season lasts 155 days in a typical year, longer than at 60% of the 52 Maine stations; it reaches 171 days one year in ten and falls short of 137 one year in ten. On average 163 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 17, and return around September 28. Severe cold of 16°F or below comes every winter, usually between November 23 and March 28.

July is the warmest month at Rumford 1 SSE, ME, averaging 79°F by day and 58°F at night; January is the coldest at 28°F and 7°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 66% of years.

Warmth for growing adds up to 2,078 growing degree days a year (base 50°F), more than at 58% of the 52 Maine stations. 30% of them (618) have built up by the end of June, and July adds the most, 575. Precipitation totals 49.0 inches a year, most in June (6.1") and least in February (2.4"); May to September bring 47% of it.

The nearest other station, Bethel 6 SSE, ME, 18 miles southwest of Rumford and 160 feet higher, has a last frost 2 days later (May 6), a first frost 4 days earlier (October 2), a season 8 days shorter.

The first measurable snow (0.1 inch or more) in Rumford usually arrives around November 17, and the last of the season around April 5. Those are the middle dates across the winters of 1991–2020 at Rumford 1 SSE, ME, 1.5 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 29 days after the last snow.

ZIP 04276 is 2 miles from Rumford 1 SSE, ME, which stands at 630 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station. The 2023 USDA Plant Hardiness Zone Map lists ZIP 04276 in zone 5a, the band where the coldest night of the year averaged -20 to -15°F (-28.9 to -26.1°C) over 1991–2020; a zone describes winter lows, not frost dates.