Sunnyside, WA 98944 Frost Dates
Frost dates for Sunnyside, WA, ZIP 98944
Typically, the last spring freeze lands around 05/01, roughly 246 days out. The first fall frost typically arrives around 10/06, about 157 frost-free days later.
Zone 7b (5 to 10°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 Sunnyside, not a forecast for this year.
What to do before the first frost
Zone 7b around Sunnyside has about 6 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.
The actual range around Sunnyside's last frost
05/01 is the middle of 30 years of NOAA records, not a promise. Plant by 04/16 and you're betting against frost in roughly 9 years out of 10. 05/18 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Sunnyside compares
Sunnyside's growing season runs about 157 days, ranking 33,256 of 40,283 US ZIP codes measured here, longest to shortest. Within WA, it ranks 579 of 700.
Learn more
the frost range explains how to read the range around Sunnyside's dates instead of trusting one, and local microclimates explains what one yard in Sunnyside can differ from the 98944 normal.