Lewiston, ME 04069 Frost Dates
Frost dates for Lewiston, ME, ZIP 04069
Typically, the last spring freeze lands around 04/28, roughly 243 days out. The first fall frost typically arrives around 10/19, about 172 frost-free days later.
Lewiston 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 Lewiston 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 04/28 isn't a guarantee
04/28 is the middle of 30 years of NOAA records, not a promise. Plant by 04/15 and you're betting against frost in roughly 9 years out of 10. 05/10 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Lewiston compares
About 172 days separate Lewiston's last and first frost, putting it 28,163 of 40,283 ZIP codes nationally. Within ME, it ranks 76 of 456.
Learn more
zone vs. frost date explains why Zone 5b and Lewiston's frost date answer different questions, and the frost range explains how to read the range around Lewiston's dates instead of trusting one.