Waterville, WA 98858 Frost Dates
Waterville, WA: when does the frost end?
Typically, the last spring freeze lands around 05/14, roughly 259 days out. Fall's first freeze usually shows up around 10/01, roughly 140 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Waterville in Zone 6b (-5 to 0°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
With roughly 5 weeks until Waterville's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Waterville's last frost
05/14 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/28 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/04 and only about 1 year in 10 sees frost after that.
Waterville against the rest of the dataset
About 140 days separate Waterville's last and first frost, putting it 37,075 of 40,283 ZIP codes nationally. Within WA, it ranks 617 of 700.
Learn more
Before leaning on 98858's figures: the frost range explains how to read the range around Waterville's dates instead of trusting one, while local microclimates explains what one yard in Waterville can differ from the 98858 normal.