Frost Dates for 15938 — Lilly, Pennsylvania

Half of springs at Ebensburg Sewage Plt, PA see their last 32°F night by May 17; only one in ten is past it by April 30, and one in ten still has one after June 1. Planting tender crops after May 25 leaves a 30% risk of a frost on them, after May 28 20%, and after June 1 10%. The 15 days between the even-odds date and the one-in-ten date is narrower than at 72% of the 176 Pennsylvania stations behind this site's ZIP pages.

In fall the first 32°F night comes by October 2 in half of years, as early as September 19 one year in ten, and holds off past October 14 one year in ten. A hard freeze of 28°F follows 11 days later, around October 13; in spring the one-in-ten date for 28°F is May 22, 10 days before the 32°F one. The freeze-free season lasts 136 days in a typical year, shorter than at 97% of the 176 Pennsylvania stations; it reaches 159 days one year in ten and falls short of 114 one year in ten. On average 157 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 14 days longer, to about May 31, and return around September 22. Severe cold of 16°F or below comes every winter, usually between November 18 and March 27.

July is the warmest month at Ebensburg Sewage Plt, PA, averaging 79°F by day and 56°F at night; January is the coldest at 33°F and 16°F. A freezing night is all but certain in every month from October to April (a 90% chance or more). From July to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 84% of years and June still brings one in 12% of years.

Warmth for growing adds up to 2,143 growing degree days a year (base 50°F), fewer than at 90% of the 176 Pennsylvania stations. 33% of them (701) have built up by the end of June, and July adds the most, 542. Precipitation totals 48.7 inches a year, most in July (4.8") and least in February (3.2"); May to September bring 45% of it.

The nearest other station, Altoona 3 W, PA, 10 miles northeast of Lilly and 620 feet lower, has a last frost 22 days earlier (April 25), a first frost 19 days later (October 21), a season 40 days longer.

The first measurable snow (0.1 inch or more) in Lilly usually arrives around November 12, and the last of the season around April 6. Those are the middle dates across the winters of 1991–2020 at Ebensburg Sewage Plt, PA, 6.7 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 15938 is 7 miles from Ebensburg Sewage Plt, PA, which stands at 1,940 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 6 other ZIP codes share the station; its figures are presented in full for 15931 (Ebensburg). The 2023 USDA Plant Hardiness Zone Map lists ZIP 15938 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.