Sultan, WA 98293 Frost Dates
Frost dates for Sultan, WA, ZIP 98293
Around 04/15 is the usual last spring frost, about 230 days away. The first fall frost typically arrives around 10/25, about 192 frost-free days later.
Zone 8b (15 to 20°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 Sultan, not a forecast for this year.
What to do before the first frost
Zone 8b around Sultan has about 8 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
04/15 is the middle of 30 years of NOAA records, not a promise. Plant by 03/25 and you're betting against frost in roughly 9 years out of 10. 05/07 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Sultan compares
Sultan's growing season runs about 192 days, ranking 20,254 of 40,283 US ZIP codes measured here, longest to shortest. Within WA, it ranks 390 of 700.
Learn more
the frost range explains how to read the range around Sultan's dates instead of trusting one, and local microclimates explains what one yard in Sultan can differ from the 98293 normal.