Dauphin, PA 17018 Frost Dates
17018, near Dauphin, PA: the frost window
Typically, the last spring freeze lands around 04/09, roughly 224 days out. Fall's first freeze usually shows up around 11/01, roughly 205 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 Dauphin, not a forecast for this year.
Stretching the season past the first frost
Dauphin's growing season runs out in roughly 9 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
04/09 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/27 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/25 and only about 1 year in 10 sees frost after that.
Dauphin against the rest of the dataset
Dauphin's growing season runs about 205 days, ranking 16,377 of 40,283 US ZIP codes measured here, longest to shortest. Within PA, it ranks 181 of 2,088.
Learn more
Two guides worth reading on 17018: local microclimates, on what one yard in Dauphin can differ from the 17018 normal, and zone vs. frost date, on why Zone 7a and Dauphin's frost date answer different questions.