Frost Dates for 15461 — Masontown, Pennsylvania

Half of springs at Grays Landing, PA see their last 32°F night by April 28; only one in ten is past it by April 15, and one in ten still has one after May 14. Planting tender crops after May 4 leaves a 30% risk of a frost on them, after May 8 20%, and after May 14 10%. The 16 days between the even-odds date and the one-in-ten date is narrower than at 51% of the 176 Pennsylvania stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 21 in half of years, as early as October 9 one year in ten, and holds off past November 1 one year in ten. A hard freeze of 28°F follows 10 days later, around October 31; in spring the one-in-ten date for 28°F is May 1, 13 days before the 32°F one. The freeze-free season lasts 175 days in a typical year, shorter than at 48% of the 176 Pennsylvania stations; it reaches 193 days one year in ten and falls short of 156 one year in ten. On average 124 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 10 days longer, to about May 8, and return around October 11. Severe cold of 16°F or below comes every winter, usually between December 3 and March 11.

July is the warmest month at Grays Landing, PA, averaging 84°F by day and 62°F at night; January is the coldest at 39°F and 21°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 39% of years.

Warmth for growing adds up to 3,105 growing degree days a year (base 50°F), more than at 60% of the 176 Pennsylvania stations. 34% of them (1,057) have built up by the end of June, and July adds the most, 718. Precipitation totals 42.2 inches a year, most in June (4.3") and least in February (2.6"); May to September bring 47% of it.

The nearest other station, Pt Marion Lock 8, PA, 8 miles south of Masontown, has a last frost 2 days later (April 30), a first frost 2 days later (October 23), a season 2 days longer.

The first measurable snow (0.1 inch or more) in Masontown usually arrives around December 9, and the last of the season around March 7. Those are the middle dates across the winters of 1991–2020 at Grays Landing, PA, 4.5 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 52 days after the last snow.

ZIP 15461 is 5 miles from Grays Landing, PA, which stands at 800 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 2 other ZIP codes share the station; its figures are presented in full for 15320 (Carmichaels). The 2023 USDA Plant Hardiness Zone Map lists ZIP 15461 in zone 6b, the band where the coldest night of the year averaged -5 to 0°F (-20.6 to -17.8°C) over 1991–2020; a zone describes winter lows, not frost dates.