Unionville, PA 16835 Frost Dates
Unionville, PA: when does the frost end?
Typically, the last spring freeze lands around 04/20, roughly 235 days out. Fall's first freeze usually shows up around 10/26, roughly 187 days after the last spring frost.
Unionville sits in USDA Zone 6b (-5 to 0°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
With roughly 8 weeks until Unionville's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
04/20 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/07 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/06 and only about 1 year in 10 sees frost after that.
Unionville against the rest of the dataset
At roughly 187 frost-free days, Unionville places 22,602 of 40,283 ZIP codes in this dataset. Within PA, it ranks 625 of 2,088.
Learn more
Before leaning on 16835's figures: the frost range explains how to read the range around Unionville's dates instead of trusting one, while local microclimates explains what one yard in Unionville can differ from the 16835 normal.