Tieton, WA 98923 Frost Dates
When can you plant in Tieton, WA?
Typically, the last spring freeze lands around 04/08, roughly 223 days out. The first fall frost typically arrives around 10/23, about 196 frost-free days later.
The USDA Plant Hardiness Zone Map puts Tieton in Zone 7a (0 to 5°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
About 8 weeks of growing season left in Tieton before the first fall frost — a cold frame or row cover can stretch harvest weeks past that date.
Why 04/08 isn't a guarantee
04/08 is the middle of 30 years of NOAA records, not a promise. Plant by 03/23 and you're betting against frost in roughly 9 years out of 10. 04/28 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Tieton compares
At roughly 196 frost-free days, Tieton places 19,011 of 40,283 ZIP codes in this dataset. Within WA, it ranks 353 of 700.
Learn more
local microclimates covers what one yard in Tieton can differ from the 98923 normal. zone vs. frost date covers why Zone 7a and Tieton's frost date answer different questions.