Keene, NH 03604 Frost Dates
03604, near Keene, NH: the frost window
The last spring frost here typically falls around 05/14, about 259 days from today. 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.
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
At roughly 138 frost-free days, Keene places 37,351 of 40,283 ZIP codes in this dataset. Within NH, it ranks 203 of 260.
Learn more
Two guides worth reading on 03604: the frost range, on how to read the range around Keene's dates instead of trusting one, and local microclimates, on what one yard in Keene can differ from the 03604 normal.