Concord, NH 03278 Frost Dates
Frost dates for Concord, NH, ZIP 03278
Typically, the last spring freeze lands around 05/14, roughly 259 days out. The first fall frost typically arrives around 09/29, about 138 frost-free days later.
Zone 5b (-15 to -10°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 Concord, not a forecast for this year.
What to do before the first frost
Zone 5b around Concord has about 5 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.
How much risk comes with planting early here
05/14 is the middle of 30 years of NOAA records, not a promise. Plant by 04/30 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 Concord compares
At roughly 138 frost-free days, Concord places 37,337 of 40,283 ZIP codes in this dataset. Within NH, it ranks 189 of 260.
Learn more
the frost range explains how to read the range around Concord's dates instead of trusting one, and local microclimates explains what one yard in Concord can differ from the 03278 normal.