Sammamish, WA 98053 Frost Dates
Sammamish, WA: when does the frost end?
Typically, the last spring freeze lands around 03/08, roughly 192 days out. Fall's first freeze usually shows up around 11/23, roughly 259 days after the last spring frost.
Sammamish 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.
Stretching the season past the first frost
With roughly 12 weeks until Sammamish's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
How much risk comes with planting early here
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.
Sammamish against the rest of the dataset
Sammamish's growing season runs about 259 days, ranking 6,545 of 40,283 US ZIP codes measured here, longest to shortest. Within WA, it ranks 35 of 700.
Learn more
Before leaning on 98053's figures: local microclimates explains what one yard in Sammamish can differ from the 98053 normal, while zone vs. frost date explains why Zone 8b and Sammamish's frost date answer different questions.