Frost Dates for 16506 — Erie, Pennsylvania

Half of springs at Erie International Airport, PA see their last 32°F night by April 26; only one in ten is past it by April 10, and one in ten still has one after May 13. Planting tender crops after May 2 leaves a 30% risk of a frost on them, after May 6 20%, and after May 13 10%. The 17 days between the even-odds date and the one-in-ten date is wider than at 50% of the 176 Pennsylvania stations behind this site's ZIP pages.

In fall the first 32°F night comes by November 4 in half of years, as early as October 21 one year in ten, and holds off past November 17 one year in ten. A hard freeze of 28°F follows 12 days later, around November 16; in spring the one-in-ten date for 28°F is April 25, 18 days before the 32°F one. The freeze-free season lasts 192 days in a typical year, longer than at 83% of the 176 Pennsylvania stations; it reaches 214 days one year in ten and falls short of 171 one year in ten. On average 111 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 7, and return around October 23. Severe cold of 16°F or below comes every winter, usually between December 22 and March 13.

July is the warmest month at Erie International Airport, PA, averaging 81°F by day and 64°F at night; January is the coldest at 35°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 35% of years.

Warmth for growing adds up to 3,010 growing degree days a year (base 50°F), more than at 53% of the 176 Pennsylvania stations. 32% of them (955) have built up by the end of June, and July adds the most, 702. Precipitation totals 43.1 inches a year, most in October (4.4") and least in February (2.5"); May to September bring 42% of it.

The nearest other station, Union City Filtration Plant, PA, 19 miles southeast of Erie and 670 feet higher, has a last frost 11 days later (May 7), a first frost 25 days earlier (October 10), a season 37 days shorter.

The first measurable snow (0.1 inch or more) in Erie usually arrives around November 11, and the last of the season around April 9. Those are the middle dates across the winters of 1991–2020 at Erie International Airport, PA, 2 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 17 days after the last snow.

ZIP 16506 is 2 miles from Erie International Airport, PA, which stands at 730 feet, the nearest NOAA station that publishes freeze probabilities for 1991–2020. 16 other ZIP codes share the station; its figures are presented in full for 16509 (Erie). The 2023 USDA Plant Hardiness Zone Map lists ZIP 16506 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.