FrostDateCheck

Federal Way, WA 98422 Frost Dates

Frost dates for Federal Way, WA, ZIP 98422

Zone 8b

The last spring frost here typically falls around 03/08, about 192 days from today. The first fall frost typically arrives around 11/14, about 250 frost-free days later.

Federal Way sits in USDA Zone 8b (15 to 20°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 8b around Federal Way has about 11 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 03/08 isn't a guarantee

03/08 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. 03/31 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Federal Way compares

Federal Way's growing season runs about 250 days, ranking 7,422 of 40,283 US ZIP codes measured here, longest to shortest. Within WA, it ranks 86 of 700.

Learn more

the frost range explains how to read the range around Federal Way's dates instead of trusting one, and local microclimates explains what one yard in Federal Way can differ from the 98422 normal.