Lilly, PA 15938 Frost Dates
15938, near Lilly, PA: the frost window
Around 04/29 is the usual last spring frost, about 244 days away. Fall's first freeze usually shows up around 10/21, roughly 176 days after the last spring frost.
Zone 6a (-10 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 Lilly, not a forecast for this year.
Stretching the season past the first frost
Lilly's growing season runs out in roughly 8 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
04/29 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/14 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/17 and only about 1 year in 10 sees frost after that.
Lilly against the rest of the dataset
Lilly's growing season runs about 176 days, ranking 26,560 of 40,283 US ZIP codes measured here, longest to shortest. Within PA, it ranks 1,073 of 2,088.
Learn more
Two guides worth reading on 15938: local microclimates, on what one yard in Lilly can differ from the 15938 normal, and zone vs. frost date, on why Zone 6a and Lilly's frost date answer different questions.