Frost Dates for 16373 — Emlenton, Pennsylvania

Half of springs at Clarion 3 SW, PA see their last 32°F night by May 9; only one in ten is past it by April 24, and one in ten still has one after May 24. Planting tender crops after May 16 leaves a 30% risk of a frost on them, after May 20 20%, and after May 24 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 11 in half of years, as early as September 30 one year in ten, and holds off past October 26 one year in ten. A hard freeze of 28°F follows 13 days later, around October 24; in spring the one-in-ten date for 28°F is May 15, 9 days before the 32°F one. The freeze-free season lasts 154 days in a typical year, shorter than at 84% of the 176 Pennsylvania stations; it reaches 174 days one year in ten and falls short of 135 one year in ten. On average 155 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 11 days longer, to about May 20, and return around October 2. Severe cold of 16°F or below comes every winter, usually between November 29 and March 24.

July is the warmest month at Clarion 3 SW, PA, averaging 82°F by day and 57°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 June to August the chance of a 32°F night stays under 10% each month. In spring, May still brings one in 76% of years.

Warmth for growing adds up to 2,453 growing degree days a year (base 50°F), fewer than at 81% of the 176 Pennsylvania stations. 33% of them (804) have built up by the end of June, and July adds the most, 608. Precipitation totals 46.9 inches a year, most in July (5.3") and least in February (2.7"); May to September bring 47% of it.

The nearest other station, Franklin, PA, 16 miles northwest of Emlenton, has a last frost 7 days earlier (May 2), a first frost 12 days later (October 23), a season 17 days longer.

The first measurable snow (0.1 inch or more) in Emlenton usually arrives around November 30, and the last of the season around March 23. Those are the middle dates across the winters of 1991–2020 at Clarion 3 SW, PA, 13.7 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 47 days after the last snow.

ZIP 16373 is 14 miles from Clarion 3 SW, PA, which stands at 1,040 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 16214 (Clarion). The 2023 USDA Plant Hardiness Zone Map lists ZIP 16373 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.