Dover, NH 03042 Frost Dates
03042, near Dover, NH: the frost window
Around 05/07 is the usual last spring frost, about 252 days away. Fall's first freeze usually shows up around 10/04, roughly 148 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Dover 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
Dover'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.
How much risk comes with planting early here
05/07 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/25 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/21 and only about 1 year in 10 sees frost after that.
Dover against the rest of the dataset
About 148 days separate Dover's last and first frost, putting it 35,623 of 40,283 ZIP codes nationally. Within NH, it ranks 133 of 260.
Learn more
Two guides worth reading on 03042: the frost range, on how to read the range around Dover's dates instead of trusting one, and local microclimates, on what one yard in Dover can differ from the 03042 normal.