Coopersburg, PA 18034 Frost Dates
Frost dates for Coopersburg, PA, ZIP 18034
Typically, the last spring freeze lands around 04/20, roughly 235 days out. The first fall frost typically arrives around 10/24, about 184 frost-free days later.
The USDA Plant Hardiness Zone Map puts Coopersburg in Zone 7a (0 to 5°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 7a around Coopersburg 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 04/20 isn't a guarantee
04/20 is the middle of 30 years of NOAA records, not a promise. Plant by 04/06 and you're betting against frost in roughly 9 years out of 10. 05/06 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Coopersburg compares
Coopersburg's growing season runs about 184 days, ranking 23,559 of 40,283 US ZIP codes measured here, longest to shortest. Within PA, it ranks 803 of 2,088.
Learn more
local microclimates explains what one yard in Coopersburg can differ from the 18034 normal, and zone vs. frost date explains why Zone 7a and Coopersburg's frost date answer different questions.