Mosier, OR 97040 Frost Dates
Frost dates for Mosier, OR, ZIP 97040
Typically, the last spring freeze lands around 04/20, roughly 235 days out. The first fall frost typically arrives around 10/13, about 177 frost-free days later.
Mosier sits in USDA Zone 7b (5 to 10°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.
What to do before the first frost
Zone 7b around Mosier has about 7 weeks left before the first fall frost — that's the usual window to get a cold frame up if you want to keep harvesting past it.
The actual range around Mosier's last frost
04/20 is the middle of 30 years of NOAA records, not a promise. Plant by 03/29 and you're betting against frost in roughly 9 years out of 10. 05/09 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Mosier compares
At roughly 177 frost-free days, Mosier places 26,229 of 40,283 ZIP codes in this dataset. Within OR, it ranks 305 of 463.
Learn more
zone vs. frost date explains why Zone 7b and Mosier's frost date answer different questions, and the frost range explains how to read the range around Mosier's dates instead of trusting one.