Norwalk, CT 06858 Frost Dates
Frost dates for Norwalk, CT, ZIP 06858
The last spring frost here typically falls around 04/17, about 232 days from today. The first fall frost typically arrives around 10/23, about 188 frost-free days later.
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 Norwalk, not a forecast for this year.
What to do before the first frost
Zone 7a around Norwalk has about 8 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.
Why 04/17 isn't a guarantee
04/17 is the middle of 30 years of NOAA records, not a promise. Plant by 04/03 and you're betting against frost in roughly 9 years out of 10. 05/02 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Norwalk compares
At roughly 188 frost-free days, Norwalk places 21,814 of 40,283 ZIP codes in this dataset. Within CT, it ranks 225 of 391.
Learn more
the frost range explains how to read the range around Norwalk's dates instead of trusting one, and local microclimates explains what one yard in Norwalk can differ from the 06858 normal.