Kelso, WA 98626 Frost Dates
Kelso, WA: when does the frost end?
Typically, the last spring freeze lands around 04/08, roughly 223 days out. Fall's first freeze usually shows up around 11/05, roughly 210 days after the last spring frost.
Kelso sits in USDA Zone 8b (15 to 20°F average annual minimum). The dates above are NOAA's 1991-2020 normal at the nearest reporting station, a 30-year average, not a forecast.
Stretching the season past the first frost
With roughly 10 weeks until Kelso's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Kelso's last frost
04/08 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/11 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 05/02 and only about 1 year in 10 sees frost after that.
Kelso against the rest of the dataset
Kelso's growing season runs about 210 days, ranking 14,983 of 40,283 US ZIP codes measured here, longest to shortest. Within WA, it ranks 273 of 700.
Learn more
Before leaning on 98626's figures: zone vs. frost date explains why Zone 8b and Kelso's frost date answer different questions, while the frost range explains how to read the range around Kelso's dates instead of trusting one.