Westbrook, ME 04093 Frost Dates
Frost dates for Westbrook, ME, ZIP 04093
Typically, the last spring freeze lands around 05/07, roughly 252 days out. The first fall frost typically arrives around 10/04, about 148 frost-free days later.
Westbrook sits in USDA Zone 5b (-15 to -10°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 5b around Westbrook has about 5 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.
How much risk comes with planting early here
05/07 is the middle of 30 years of NOAA records, not a promise. Plant by 04/28 and you're betting against frost in roughly 9 years out of 10. 05/18 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Westbrook compares
Westbrook's growing season runs about 148 days, ranking 35,664 of 40,283 US ZIP codes measured here, longest to shortest. Within ME, it ranks 315 of 456.
Learn more
zone vs. frost date explains why Zone 5b and Westbrook's frost date answer different questions, and the frost range explains how to read the range around Westbrook's dates instead of trusting one.