Marlborough, MA 02471 Frost Dates
Frost dates for Marlborough, MA, ZIP 02471
The last spring frost here typically falls around 05/02, about 247 days from today. The first fall frost typically arrives around 10/06, about 156 frost-free days later.
Marlborough 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.
What to do before the first frost
Zone 6b around Marlborough 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.
The actual range around Marlborough's last frost
05/02 is the middle of 30 years of NOAA records, not a promise. Plant by 04/22 and you're betting against frost in roughly 9 years out of 10. 05/16 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Marlborough compares
About 156 days separate Marlborough's last and first frost, putting it 33,535 of 40,283 ZIP codes nationally. Within MA, it ranks 635 of 712.
Learn more
the frost range explains how to read the range around Marlborough's dates instead of trusting one, and local microclimates explains what one yard in Marlborough can differ from the 02471 normal.