Frost Dates for 03903 — Eliot, Maine

Half of springs at Durham 2 N, NH see their last 32°F night by May 3; only one in ten is past it by April 23, and one in ten still has one after May 16. Planting tender crops after May 8 leaves a 30% risk of a frost on them, after May 12 20%, and after May 16 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 10 in half of years, as early as September 27 one year in ten, and holds off past October 25 one year in ten. A hard freeze of 28°F follows 13 days later, around October 23; in spring the one-in-ten date for 28°F is May 3, 13 days before the 32°F one. The freeze-free season lasts 158 days in a typical year, longer than at 67% of the 52 Maine stations; it reaches 175 days one year in ten and falls short of 140 one year in ten. On average 150 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 15, and return around September 29. Severe cold of 16°F or below comes every winter, usually between December 1 and March 17.

July is the warmest month at Durham 2 N, NH, averaging 81°F by day and 59°F at night; January is the coldest at 32°F and 15°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 63% of years.

Warmth for growing adds up to 2,266 growing degree days a year (base 50°F), more than at 81% of the 52 Maine stations. 29% of them (656) have built up by the end of June, and July adds the most, 612. Precipitation totals 48.0 inches a year, most in October (4.8") and least in January (3.4"); May to September bring 40% of it.

The nearest other station, Durham, NH, 8 miles west of Eliot, has a last frost 5 days later (May 8), a first frost 6 days earlier (October 4), a season 10 days shorter.

The first measurable snow (0.1 inch or more) in Eliot usually arrives around December 5, and the last of the season around March 23. Those are the middle dates across the winters of 1991–2020 at Eliot, ME, 2.5 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 41 days after the last snow.

ZIP 03903 is 7 miles from Durham 2 N, NH, which stands at 119 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 4 other ZIP codes share the station; its figures are presented in full for 03820 (Dover). The 2023 USDA Plant Hardiness Zone Map lists ZIP 03903 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.