Lancaster, PA 17608 Frost Dates
Frost dates for Lancaster, PA, ZIP 17608
Around 04/18 is the usual last spring frost, about 233 days away. The first fall frost typically arrives around 10/25, about 186 frost-free days later.
Lancaster sits in USDA Zone 7a (0 to 5°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
Zone 7a around Lancaster has about 8 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 04/18 isn't a guarantee
04/18 is the middle of 30 years of NOAA records, not a promise. Plant by 04/04 and you're betting against frost in roughly 9 years out of 10. 05/05 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Lancaster compares
At roughly 186 frost-free days, Lancaster places 22,699 of 40,283 ZIP codes in this dataset. Within PA, it ranks 637 of 2,088.
Learn more
the frost range explains how to read the range around Lancaster's dates instead of trusting one, and local microclimates explains what one yard in Lancaster can differ from the 17608 normal.