New Haven, CT 06533 Frost Dates
06533, near New Haven, CT: the frost window
The last spring frost here typically falls around 04/17, about 232 days from today. Fall's first freeze usually shows up around 10/27, roughly 193 days after the last spring frost.
Zone 7a (0 to 5°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 New Haven, not a forecast for this year.
Stretching the season past the first frost
New Haven's growing season runs out in roughly 9 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
04/17 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/02 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/01 and only about 1 year in 10 sees frost after that.
New Haven against the rest of the dataset
New Haven's growing season runs about 193 days, ranking 19,706 of 40,283 US ZIP codes measured here, longest to shortest. Within CT, it ranks 82 of 391.
Learn more
Two guides worth reading on 06533: local microclimates, on what one yard in New Haven can differ from the 06533 normal, and zone vs. frost date, on why Zone 7a and New Haven's frost date answer different questions.