Ambler, PA 19422 Frost Dates
Frost dates for Ambler, PA, ZIP 19422
Around 04/08 is the usual last spring frost, about 223 days away. The first fall frost typically arrives around 10/31, about 203 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 Ambler, not a forecast for this year.
What to do before the first frost
Zone 7a around Ambler has about 9 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.
How much risk comes with planting early here
04/08 is the middle of 30 years of NOAA records, not a promise. Plant by 03/28 and you're betting against frost in roughly 9 years out of 10. 04/23 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Ambler compares
About 203 days separate Ambler's last and first frost, putting it 16,882 of 40,283 ZIP codes nationally. Within PA, it ranks 194 of 2,088.
Learn more
zone vs. frost date explains why Zone 7a and Ambler's frost date answer different questions, and the frost range explains how to read the range around Ambler's dates instead of trusting one.