Grass Valley, OR 97033 Frost Dates
Grass Valley, OR: when does the frost end?
The last spring frost here typically falls around 05/15, about 260 days from today. Fall's first freeze usually shows up around 10/11, roughly 147 days after the last spring frost.
Grass Valley sits in USDA Zone 7a (0 to 5°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 6 weeks until Grass Valley's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Grass Valley's last frost
05/15 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 04/29 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 06/06 and only about 1 year in 10 sees frost after that.
Grass Valley against the rest of the dataset
About 147 days separate Grass Valley's last and first frost, putting it 35,990 of 40,283 ZIP codes nationally. Within OR, it ranks 355 of 463.
Learn more
Before leaning on 97033's figures: the frost range explains how to read the range around Grass Valley's dates instead of trusting one, while local microclimates explains what one yard in Grass Valley can differ from the 97033 normal.