Asotin, WA 99402 Frost Dates
Frost dates for Asotin, WA, ZIP 99402
Around 04/06 is the usual last spring frost, about 221 days away. The first fall frost typically arrives around 10/26, about 200 frost-free days later.
The USDA Plant Hardiness Zone Map puts Asotin in Zone 7a (0 to 5°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 7a around Asotin 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 Asotin'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 Asotin compares
About 200 days separate Asotin's last and first frost, putting it 17,846 of 40,283 ZIP codes nationally. Within WA, it ranks 328 of 700.
Learn more
the frost range explains how to read the range around Asotin's dates instead of trusting one, and local microclimates explains what one yard in Asotin can differ from the 99402 normal.