Clarkston, WA 99403 Frost Dates
Frost dates for Clarkston, WA, ZIP 99403
Typically, the last spring freeze lands around 04/06, roughly 221 days out. The first fall frost typically arrives around 10/26, about 200 frost-free days later.
The USDA Plant Hardiness Zone Map puts Clarkston in Zone 7b (5 to 10°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
Zone 7b around Clarkston has about 8 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.
The actual range around Clarkston's last frost
04/06 is the middle of 30 years of NOAA records, not a promise. Plant by 03/20 and you're betting against frost in roughly 9 years out of 10. 04/26 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Clarkston compares
About 200 days separate Clarkston's last and first frost, putting it 17,758 of 40,283 ZIP codes nationally. Within WA, it ranks 319 of 700.
Learn more
the frost range explains how to read the range around Clarkston's dates instead of trusting one, and local microclimates explains what one yard in Clarkston can differ from the 99403 normal.