Keene, NH 03435 Frost Dates
Keene, NH: when does the frost end?
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.
The USDA Plant Hardiness Zone Map puts Keene in Zone 5b (-15 to -10°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
With roughly 5 weeks until Keene's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
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 37,341 of 40,283 ZIP codes nationally. Within NH, it ranks 193 of 260.
Learn more
Before leaning on 03435's figures: local microclimates explains what one yard in Keene can differ from the 03435 normal, while zone vs. frost date explains why Zone 5b and Keene's frost date answer different questions.