Frost Dates for 04061 — North Waterboro, Maine

Half of springs at Hollis, ME see their last 32°F night by May 14; only one in ten is past it by May 3, and one in ten still has one after May 28. Planting tender crops after May 20 leaves a 30% risk of a frost on them, after May 23 20%, and after May 28 10%. The 14 days between the even-odds date and the one-in-ten date is wider than at 69% of the 52 Maine stations behind this site's ZIP pages.

In fall the first 32°F night comes by September 30 in half of years, as early as September 16 one year in ten, and holds off past October 12 one year in ten. A hard freeze of 28°F follows 10 days later, around October 10; in spring the one-in-ten date for 28°F is May 13, 15 days before the 32°F one. The freeze-free season lasts 136 days in a typical year, shorter than at 83% of the 52 Maine stations; it reaches 152 days one year in ten and falls short of 118 one year in ten. On average 184 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 27, and return around September 19. Severe cold of 16°F or below comes every winter, usually between November 19 and March 29.

July is the warmest month at Hollis, ME, averaging 80°F by day and 57°F at night; January is the coldest at 29°F and 8°F. A freezing night is all but certain in every month from October to May (a 90% chance or more). From June to August the chance of a 32°F night stays under 10% each month.

Warmth for growing adds up to 1,960 growing degree days a year (base 50°F), fewer than at 56% of the 52 Maine stations. 29% of them (561) have built up by the end of June, and July adds the most, 570. Precipitation totals 52.2 inches a year, most in October (5.8") and least in January (3.6"); May to September bring 39% of it.

The nearest other station, West Buxton 2 NNW, ME, 7 miles northeast of North Waterboro, has a last frost 7 days earlier (May 7), a first frost 4 days later (October 4), a season 12 days longer.

The first measurable snow (0.1 inch or more) in North Waterboro usually arrives around November 24, and the last of the season around April 12. Those are the middle dates across the winters of 1991–2020 at Hollis, ME, 2.8 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 32 days after the last snow.

ZIP 04061 is 3 miles from Hollis, ME, which stands at 304 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 04042 (Hollis Center). The 2023 USDA Plant Hardiness Zone Map lists ZIP 04061 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.