Frost Dates for 19022 — Eddystone, Pennsylvania

Half of springs at Marcus Hook, PA see their last 32°F night by March 30; only one in ten is past it by March 16, and one in ten still has one after April 9. Planting tender crops after April 3 leaves a 30% risk of a frost on them, after April 5 20%, and after April 9 10%. The 10 days between the even-odds date and the one-in-ten date is the narrowest of the 176 Pennsylvania stations behind this site's ZIP pages, so the end of frost is fairly predictable.

In fall the first 32°F night comes by November 16 in half of years, as early as November 2 one year in ten, and holds off past December 2 one year in ten. A hard freeze of 28°F follows 12 days later, around November 28; in spring the one-in-ten date for 28°F is March 31, 9 days before the 32°F one. The freeze-free season lasts 230 days in a typical year, longer than at 99% of the 176 Pennsylvania stations; it reaches 253 days one year in ten and falls short of 212 one year in ten. On average 65 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 April 9, and return around November 2. Severe cold of 16°F or below comes in 96% of winters, usually between January 9 and February 16.

July is the warmest month at Marcus Hook, PA, averaging 89°F by day and 70°F at night; January is the coldest at 43°F and 27°F. A freezing night is all but certain in every month from December to March (a 90% chance or more). From May to October the chance of a 32°F night stays under 10% each month. In spring, April still brings one in 42% of years.

Warmth for growing adds up to 4,198 growing degree days a year (base 50°F), more than at 99% of the 176 Pennsylvania stations. 34% of them (1,429) have built up by the end of June, and July adds the most, 913. Precipitation totals 41.8 inches a year, most in July (4.8") and least in February (2.2"); May to September bring 46% of it.

The nearest other station, Philadelphia International Airport, PA, 6 miles east of Eddystone, has a last frost 3 days later (April 2), a first frost 6 days earlier (November 10), a season 6 days shorter.

The first measurable snow (0.1 inch or more) in Eddystone usually arrives around December 19, and the last of the season around March 21. Those are the middle dates across the winters of 1991–2020 at Philadelphia International Airport, PA, 5.8 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 9 days after the last snow.

ZIP 19022 is 5 miles from Marcus Hook, PA, which stands at 10 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 11 other ZIP codes share the station; its figures are presented in full for 19063 (Media). The 2023 USDA Plant Hardiness Zone Map lists ZIP 19022 in zone 8a, the band where the coldest night of the year averaged 10 to 15°F (-12.2 to -9.4°C) over 1991–2020; a zone describes winter lows, not frost dates.