Tigard, OR 97078 Frost Dates
Tigard, OR: when does the frost end?
Typically, the last spring freeze lands around 02/11, roughly 167 days out. Fall's first freeze usually shows up around 12/05, roughly 303 days after the last spring frost.
The USDA Plant Hardiness Zone Map puts Tigard in Zone 8b (15 to 20°F average annual minimum); frost dates are NOAA's 1991-2020 station normal, not this year's forecast.
Stretching the season past the first frost
With roughly 14 weeks until Tigard's first fall frost, a row cover or cold frame is what stretches the last few weeks of harvest here.
The actual range around Tigard's last frost
02/11 is the middle of 30 years of NOAA records, not a promise. Getting tender plants in by 03/05 carries real risk, frost has hit that late in about 9 of 10 years here. Wait until 12/26 and only about 1 year in 10 sees frost after that.
Tigard against the rest of the dataset
About 303 days separate Tigard's last and first frost, putting it 3,776 of 40,283 ZIP codes nationally. Within OR, it ranks 23 of 463.
Learn more
Before leaning on 97078's figures: local microclimates explains what one yard in Tigard can differ from the 97078 normal, while zone vs. frost date explains why Zone 8b and Tigard's frost date answer different questions.