Chelan, WA 98817 Frost Dates
Frost dates for Chelan, WA, ZIP 98817
Around 05/14 is the usual last spring frost, about 259 days away. The first fall frost typically arrives around 10/01, about 140 frost-free days later.
Chelan sits in USDA Zone 7b (5 to 10°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
What to do before the first frost
Zone 7b around Chelan has about 5 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 05/14 isn't a guarantee
05/14 is the middle of 30 years of NOAA records, not a promise. Plant by 04/28 and you're betting against frost in roughly 9 years out of 10. 06/04 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Chelan compares
Chelan's growing season runs about 140 days, ranking 37,051 of 40,283 US ZIP codes measured here, longest to shortest. Within WA, it ranks 614 of 700.
Learn more
local microclimates explains what one yard in Chelan can differ from the 98817 normal, and zone vs. frost date explains why Zone 7b and Chelan's frost date answer different questions.