Frost Dates for 14510 — Mount Morris, New York

Half of springs at Mt Morris 2 W, NY see their last 32°F night by April 30; only one in ten is past it by April 17, and one in ten still has one after May 13. Planting tender crops after May 5 leaves a 30% risk of a frost on them, after May 9 20%, and after May 13 10%. The 13 days between the even-odds date and the one-in-ten date is narrower than at 83% of the 173 New York stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 17 in half of years, as early as October 1 one year in ten, and holds off past November 2 one year in ten. A hard freeze of 28°F follows 15 days later, around November 1; in spring the one-in-ten date for 28°F is May 2, 11 days before the 32°F one. The freeze-free season lasts 170 days in a typical year, longer than at 65% of the 173 New York stations; it reaches 190 days one year in ten and falls short of 148 one year in ten. On average 140 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 9 days longer, to about May 9, and return around October 4. Severe cold of 16°F or below comes every winter, usually between December 4 and March 20.

July is the warmest month at Mt Morris 2 W, NY, averaging 81°F by day and 60°F at night; January is the coldest at 31°F and 15°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 47% of years.

Warmth for growing adds up to 2,547 growing degree days a year (base 50°F), more than at 54% of the 173 New York stations. 32% of them (827) have built up by the end of June, and July adds the most, 631. Precipitation totals 33.1 inches a year, most in July (4.1") and least in February (1.5"); May to September bring 53% of it.

The nearest other station, Dansville Municipal Airport, NY, 12 miles southeast of Mount Morris and 195 feet lower, has a last frost 1 day later (May 1), a first frost 2 days later (October 19).

The first measurable snow (0.1 inch or more) in Mount Morris usually arrives around November 21, and the last of the season around March 19. Those are the middle dates across the winters of 1991–2020 at Mt Morris 2 W, NY, 3.1 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 42 days after the last snow.

ZIP 14510 is 3 miles from Mt Morris 2 W, NY, which stands at 880 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 3 other ZIP codes share the station; its figures are presented in full for 14454 (Geneseo). The 2023 USDA Plant Hardiness Zone Map lists ZIP 14510 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.