Sewickley Heights, PA 15143 Frost Dates
Frost dates for Sewickley Heights, PA, ZIP 15143
Typically, the last spring freeze lands around 04/28, roughly 243 days out. The first fall frost typically arrives around 10/18, about 172 frost-free days later.
The USDA Plant Hardiness Zone Map puts Sewickley Heights in Zone 6b (-5 to 0°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
Zone 6b around Sewickley Heights has about 7 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
Why 04/28 isn't a guarantee
04/28 is the middle of 30 years of NOAA records, not a promise. Plant by 04/15 and you're betting against frost in roughly 9 years out of 10. 05/15 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Sewickley Heights compares
At roughly 172 frost-free days, Sewickley Heights places 28,410 of 40,283 ZIP codes in this dataset. Within PA, it ranks 1,393 of 2,088.
Learn more
zone vs. frost date explains why Zone 6b and Sewickley Heights's frost date answer different questions, and the frost range explains how to read the range around Sewickley Heights's dates instead of trusting one.