DuPont, WA 98351 Frost Dates
Frost dates for DuPont, WA, ZIP 98351
Around 03/11 is the usual last spring frost, about 195 days away. The first fall frost typically arrives around 11/21, about 254 frost-free days later.
Zone 8b (15 to 20°F average annual minimum) comes from the USDA Plant Hardiness Zone Map; the frost dates above are the 1991-2020 normal at the nearest reporting NOAA station for DuPont, not a forecast for this year.
What to do before the first frost
Zone 8b around DuPont has about 12 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
Why 03/11 isn't a guarantee
03/11 is the middle of 30 years of NOAA records, not a promise. Plant by 02/15 and you're betting against frost in roughly 9 years out of 10. 04/02 is the safer bet, historically only a 1-in-10 chance of frost that late.
How DuPont compares
DuPont's growing season runs about 254 days, ranking 7,019 of 40,283 US ZIP codes measured here, longest to shortest. Within WA, it ranks 67 of 700.
Learn more
the frost range explains how to read the range around DuPont's dates instead of trusting one, and local microclimates explains what one yard in DuPont can differ from the 98351 normal.