Worcester, MA 01604 Frost Dates
01604, near Worcester, MA: the frost window
Around 04/23 is the usual last spring frost, about 238 days away. Fall's first freeze usually shows up around 10/21, roughly 181 days after the last spring frost.
Worcester 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.
Stretching the season past the first frost
Worcester's growing season runs out in roughly 8 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 04/23 isn't a guarantee
04/23 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/11 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/05 and only about 1 year in 10 sees frost after that.
Worcester against the rest of the dataset
Worcester's growing season runs about 181 days, ranking 24,395 of 40,283 US ZIP codes measured here, longest to shortest. Within MA, it ranks 220 of 712.
Learn more
Two guides worth reading on 01604: zone vs. frost date, on why Zone 6a and Worcester's frost date answer different questions, and the frost range, on how to read the range around Worcester's dates instead of trusting one.