Frost Dates for 18661 — White Haven, Pennsylvania

Half of springs at Francis E Walter Dam, PA see their last 32°F night by May 7; only one in ten is past it by April 22, and one in ten still has one after May 23. Planting tender crops after May 14 leaves a 30% risk of a frost on them, after May 18 20%, and after May 23 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 6 in half of years, as early as September 22 one year in ten, and holds off past October 22 one year in ten. A hard freeze of 28°F follows 13 days later, around October 19; in spring the one-in-ten date for 28°F is May 11, 12 days before the 32°F one. The freeze-free season lasts 153 days in a typical year, shorter than at 85% of the 176 Pennsylvania stations; it reaches 174 days one year in ten and falls short of 131 one year in ten. On average 163 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 20, and return around September 27. Severe cold of 16°F or below comes every winter, usually between November 25 and March 23.

July is the warmest month at Francis E Walter Dam, PA, averaging 79°F by day and 58°F at night; January is the coldest at 31°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 66% of years.

Warmth for growing adds up to 2,209 growing degree days a year (base 50°F), fewer than at 89% of the 176 Pennsylvania stations. 32% of them (714) have built up by the end of June, and July adds the most, 567.

The nearest other station, Wilkes-Barre International Airport, PA, 17 miles north of White Haven and 579 feet lower, has a last frost 14 days earlier (April 23), a first frost 14 days later (October 20), a season 25 days longer.

The first measurable snow (0.1 inch or more) in White Haven usually arrives around November 25, and the last of the season around April 4. Those are the middle dates across the winters of 1991–2020 at Francis E Walter Dam, PA, 3 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 33 days after the last snow.

ZIP 18661 is 3 miles from Francis E Walter Dam, PA, which stands at 1,509 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 7 other ZIP codes share the station; its figures are presented in full for 18707 (Mountain Top). The 2023 USDA Plant Hardiness Zone Map lists ZIP 18661 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.