Norristown, PA 19403 Frost Dates
Norristown, PA: when does the frost end?
The last spring frost here typically falls around 04/08, about 223 days from today. Fall's first freeze usually shows up around 10/31, roughly 203 days after the last spring frost.
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 Norristown, not a forecast for this year.
Stretching the season past the first frost
With roughly 9 weeks until Norristown's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Norristown's last frost
04/08 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/28 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/23 and only about 1 year in 10 sees frost after that.
Norristown against the rest of the dataset
Norristown's growing season runs about 203 days, ranking 16,846 of 40,283 US ZIP codes measured here, longest to shortest. Within PA, it ranks 189 of 2,088.
Learn more
Before leaning on 19403's figures: zone vs. frost date explains why Zone 7a and Norristown's frost date answer different questions, while the frost range explains how to read the range around Norristown's dates instead of trusting one.