Happy Valley, OR 97236 Frost Dates
Frost dates for Happy Valley, OR, ZIP 97236
Typically, the last spring freeze lands around 03/16, roughly 200 days out. The first fall frost typically arrives around 11/20, about 250 frost-free days later.
Happy Valley sits in USDA Zone 9a (20 to 25°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 9a around Happy Valley has about 12 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.
How much risk comes with planting early here
03/16 is the middle of 30 years of NOAA records, not a promise. Plant by 02/18 and you're betting against frost in roughly 9 years out of 10. 04/12 is the safer bet, historically only a 1-in-10 chance of frost that late.
How Happy Valley compares
Happy Valley's growing season runs about 250 days, ranking 7,463 of 40,283 US ZIP codes measured here, longest to shortest. Within OR, it ranks 69 of 463.
Learn more
zone vs. frost date explains why Zone 9a and Happy Valley's frost date answer different questions, and the frost range explains how to read the range around Happy Valley's dates instead of trusting one.