Keene, NH 03446 Frost Dates
03446, near Keene, NH: the frost window
Typically, the last spring freeze lands around 05/14, roughly 259 days out. Fall's first freeze usually shows up around 10/01, roughly 138 days after the last spring frost.
Keene 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
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.
The actual range around Keene's last frost
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
At roughly 138 frost-free days, Keene places 37,345 of 40,283 ZIP codes in this dataset. Within NH, it ranks 197 of 260.
Learn more
Two guides worth reading on 03446: local microclimates, on what one yard in Keene can differ from the 03446 normal, and zone vs. frost date, on why Zone 5b and Keene's frost date answer different questions.