Riverside, WA 98849 Frost Dates
98849, near Riverside, WA: the frost window
Around 04/30 is the usual last spring frost, about 245 days away. Fall's first freeze usually shows up around 10/07, roughly 160 days after the last spring frost.
Zone 6b (-5 to 0°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 Riverside, not a forecast for this year.
Stretching the season past the first frost
Riverside's growing season runs out in roughly 6 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.
How much risk comes with planting early here
04/30 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/14 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/15 and only about 1 year in 10 sees frost after that.
Riverside against the rest of the dataset
At roughly 160 frost-free days, Riverside places 32,506 of 40,283 ZIP codes in this dataset. Within WA, it ranks 572 of 700.
Learn more
Two guides worth reading on 98849: the frost range, on how to read the range around Riverside's dates instead of trusting one, and local microclimates, on what one yard in Riverside can differ from the 98849 normal.