Yelm, WA 98509 Frost Dates
Frost dates for Yelm, WA, ZIP 98509
Typically, the last spring freeze lands around 04/29, roughly 244 days out. The first fall frost typically arrives around 10/14, about 169 frost-free days later.
The USDA Plant Hardiness Zone Map puts Yelm in Zone 8b (15 to 20°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
What to do before the first frost
Zone 8b around Yelm 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.
Why 04/29 isn't a guarantee
04/29 is the middle of 30 years of NOAA records, not a promise. Plant by 04/11 and you're betting against frost in roughly 9 years out of 10. 05/15 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Yelm compares
About 169 days separate Yelm's last and first frost, putting it 29,371 of 40,283 ZIP codes nationally. Within WA, it ranks 519 of 700.
Learn more
the frost range explains how to read the range around Yelm's dates instead of trusting one, and local microclimates explains what one yard in Yelm can differ from the 98509 normal.