South Bethlehem, PA 16242 Frost Dates
Frost dates for South Bethlehem, PA, ZIP 16242
Around 05/10 is the usual last spring frost, about 255 days away. The first fall frost typically arrives around 10/12, about 155 frost-free days later.
South Bethlehem sits in USDA Zone 6a (-10 to -5°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.
What to do before the first frost
Zone 6a around South Bethlehem has about 6 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.
Why 05/10 isn't a guarantee
05/10 is the middle of 30 years of NOAA records, not a promise. Plant by 04/24 and you're betting against frost in roughly 9 years out of 10. 05/28 is the safer bet, historically only a 1-in-10 chance of frost that late.
How South Bethlehem compares
At roughly 155 frost-free days, South Bethlehem places 34,083 of 40,283 ZIP codes in this dataset. Within PA, it ranks 1,813 of 2,088.
Learn more
the frost range explains how to read the range around South Bethlehem's dates instead of trusting one, and local microclimates explains what one yard in South Bethlehem can differ from the 16242 normal.