Calais, ME 04492 Frost Dates
Frost dates for Calais, ME, ZIP 04492
The last spring frost here typically falls around 05/02, about 247 days from today. The first fall frost typically arrives around 10/15, about 164 frost-free days later.
Calais sits in USDA Zone 5a (-20 to -15°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 5a around Calais has about 7 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 05/02 isn't a guarantee
05/02 is the middle of 30 years of NOAA records, not a promise. Plant by 04/21 and you're betting against frost in roughly 9 years out of 10. 05/12 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Calais compares
Calais's growing season runs about 164 days, ranking 30,955 of 40,283 US ZIP codes measured here, longest to shortest. Within ME, it ranks 135 of 456.
Learn more
local microclimates explains what one yard in Calais can differ from the 04492 normal, and zone vs. frost date explains why Zone 5a and Calais's frost date answer different questions.