Keene, NH 03455 Frost Dates
03455, near Keene, NH: the frost window
Around 05/14 is the usual last spring frost, about 259 days away. Fall's first freeze usually shows up around 10/01, roughly 138 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Keene in Zone 6a (-10 to -5°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Keene's growing season runs out in roughly 5 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
Why 05/14 isn't a guarantee
05/14 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/30 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/28 and only about 1 year in 10 sees frost after that.
Keene against the rest of the dataset
About 138 days separate Keene's last and first frost, putting it 37,347 of 40,283 ZIP codes nationally. Within NH, it ranks 199 of 260.
Learn more
Two guides worth reading on 03455: zone vs. frost date, on why Zone 6a and Keene's frost date answer different questions, and the frost range, on how to read the range around Keene's dates instead of trusting one.