Lewiston, ME 04240 Frost Dates
04240, near Lewiston, ME: the frost window
The last spring frost here typically falls around 04/25, about 240 days from today. Fall's first freeze usually shows up around 10/19, roughly 177 days after the last spring frost.
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.
Stretching the season past the first frost
Lewiston's growing season runs out in roughly 7 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
04/25 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/11 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/06 and only about 1 year in 10 sees frost after that.
Lewiston against the rest of the dataset
About 177 days separate Lewiston's last and first frost, putting it 26,016 of 40,283 ZIP codes nationally. Within ME, it ranks 21 of 456.
Learn more
Two guides worth reading on 04240: local microclimates, on what one yard in Lewiston can differ from the 04240 normal, and zone vs. frost date, on why Zone 5b and Lewiston's frost date answer different questions.