Shoreline, WA 98177 Frost Dates
98177, near Shoreline, WA: the frost window
Around 03/08 is the usual last spring frost, about 192 days away. Fall's first freeze usually shows up around 11/23, roughly 259 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Shoreline in Zone 9a (20 to 25°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
Shoreline's growing season runs out in roughly 12 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
The actual range around Shoreline's last frost
03/08 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 02/13 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 03/29 and only about 1 year in 10 sees frost after that.
Shoreline against the rest of the dataset
At roughly 259 frost-free days, Shoreline places 6,549 of 40,283 ZIP codes in this dataset. Within WA, it ranks 39 of 700.
Learn more
Two guides worth reading on 98177: local microclimates, on what one yard in Shoreline can differ from the 98177 normal, and zone vs. frost date, on why Zone 9a and Shoreline's frost date answer different questions.