Sisters, OR 97759 Frost Dates
97759, near Sisters, OR: the frost window
The last spring frost here typically falls around 06/09, about 285 days from today. Fall's first freeze usually shows up around 09/14, roughly 98 days after the last spring frost.
Zone 7a (0 to 5°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 Sisters, not a forecast for this year.
Stretching the season past the first frost
Sisters's growing season runs out in roughly 2 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
06/09 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 05/17 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/26 and only about 1 year in 10 sees frost after that.
Sisters against the rest of the dataset
At roughly 98 frost-free days, Sisters places 39,758 of 40,283 ZIP codes in this dataset. Within OR, it ranks 422 of 463.
Learn more
Two guides worth reading on 97759: the frost range, on how to read the range around Sisters's dates instead of trusting one, and local microclimates, on what one yard in Sisters can differ from the 97759 normal.