Soap Lake, WA 98851 Frost Dates
Frost dates for Soap Lake, WA, ZIP 98851
Around 04/22 is the usual last spring frost, about 237 days away. The first fall frost typically arrives around 10/17, about 175 frost-free days later.
Soap Lake sits in USDA Zone 7a (0 to 5°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 7a around Soap Lake has about 7 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.
How much risk comes with planting early here
04/22 is the middle of 30 years of NOAA records, not a promise. Plant by 04/08 and you're betting against frost in roughly 9 years out of 10. 05/06 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Soap Lake compares
At roughly 175 frost-free days, Soap Lake places 27,005 of 40,283 ZIP codes in this dataset. Within WA, it ranks 472 of 700.
Learn more
local microclimates explains what one yard in Soap Lake can differ from the 98851 normal, and zone vs. frost date explains why Zone 7a and Soap Lake's frost date answer different questions.