Lynnwood, WA 98087 Frost Dates
Frost dates for Lynnwood, WA, ZIP 98087
Around 03/09 is the usual last spring frost, about 193 days away. The first fall frost typically arrives around 11/17, about 250 frost-free days later.
Zone 9a (20 to 25°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 Lynnwood, not a forecast for this year.
What to do before the first frost
Zone 9a around Lynnwood 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 03/09 isn't a guarantee
03/09 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. 03/29 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Lynnwood compares
Lynnwood's growing season runs about 250 days, ranking 7,454 of 40,283 US ZIP codes measured here, longest to shortest. Within WA, it ranks 95 of 700.
Learn more
zone vs. frost date explains why Zone 9a and Lynnwood's frost date answer different questions, and the frost range explains how to read the range around Lynnwood's dates instead of trusting one.