Issaquah, WA 98027 Frost Dates
Issaquah, WA: when does the frost end?
Typically, the last spring freeze lands around 03/30, roughly 214 days out. Fall's first freeze usually shows up around 11/07, roughly 223 days after the last spring frost.
Issaquah 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 10 weeks until Issaquah's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Issaquah's last frost
03/30 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/04 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 04/21 and only about 1 year in 10 sees frost after that.
Issaquah against the rest of the dataset
About 223 days separate Issaquah's last and first frost, putting it 12,021 of 40,283 ZIP codes nationally. Within WA, it ranks 230 of 700.
Learn more
Before leaning on 98027's figures: the frost range explains how to read the range around Issaquah's dates instead of trusting one, while local microclimates explains what one yard in Issaquah can differ from the 98027 normal.