Downingtown, PA 19399 Frost Dates
Frost dates for Downingtown, PA, ZIP 19399
Around 04/26 is the usual last spring frost, about 241 days away. The first fall frost typically arrives around 10/18, about 174 frost-free days later.
Zone 7a (0 to 5°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for Downingtown, not a forecast for this year.
What to do before the first frost
Zone 7a around Downingtown 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.
The actual range around Downingtown's last frost
04/26 is the middle of 30 years of NOAA records, not a promise. Plant by 04/10 and you're betting against frost in roughly 9 years out of 10. 05/11 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Downingtown compares
About 174 days separate Downingtown's last and first frost, putting it 27,421 of 40,283 ZIP codes nationally. Within PA, it ranks 1,296 of 2,088.
Learn more
the frost range explains how to read the range around Downingtown's dates instead of trusting one, and local microclimates explains what one yard in Downingtown can differ from the 19399 normal.