FrostDateCheck

Twisp, WA 98814 Frost Dates

98814, near Twisp, WA: the frost window

Zone 6b

The last spring frost here typically falls around 05/15, about 260 days from today. Fall's first freeze usually shows up around 09/22, roughly 127 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 Twisp, not a forecast for this year.

Stretching the season past the first frost

Twisp's growing season runs out in roughly 4 weeks — a cold frame or greenhouse kit is the usual way to keep cool-weather crops going past the first frost.

Why 05/15 isn't a guarantee

05/15 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/30 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/01 and only about 1 year in 10 sees frost after that.

Twisp against the rest of the dataset

At roughly 127 frost-free days, Twisp places 38,641 of 40,283 ZIP codes in this dataset. Within WA, it ranks 642 of 700.

Learn more

Two guides worth reading on 98814: local microclimates, on what one yard in Twisp can differ from the 98814 normal, and zone vs. frost date, on why Zone 6b and Twisp's frost date answer different questions.