Frost dates for Boston

◇ Station-based · 89/100 confidence

Last spring frost · safe

Apr 15

~10% frost risk · typical Apr 4

First fall frost · safe

Oct 31

~10% frost risk · typical Nov 9

Frost-free days

220

Apr 4 → Nov 9

Climate zone

Continental, hot summer

Köppen Dfa

The growing year

Frost-bounded season with crops mapped onto the 12-month axis.

Frost risk Growing Harvest

JAN

FEB

MAR

APR

MAY

JUN

JUL

AUG

SEP

OCT

NOV

DEC

FROST

GROWING SEASON — 220 DAYS

APR 4

NOV 9