FrostDateCheck

Portland, TX 78467 Frost Dates

Frost dates for Portland, TX, ZIP 78467

Zone 10a

Typically, the last spring freeze lands around 01/28, roughly 153 days out. The first fall frost typically arrives around 12/21, about 331 frost-free days later.

Portland sits in USDA Zone 10a (30 to 35°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 10a around Portland has about 16 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.

Why 01/28 isn't a guarantee

01/28 is the middle of 30 years of NOAA records, not a promise. Plant by 02/28 and you're betting against frost in roughly 9 years out of 10. 12/16 is the safer bet, historically only a 1-in-10 chance of frost that late.

How Portland compares

About 331 days separate Portland's last and first frost, putting it 2,941 of 40,283 ZIP codes nationally. Within TX, it ranks 127 of 2,558.

Learn more

zone vs. frost date explains why Zone 10a and Portland's frost date answer different questions, and the frost range explains how to read the range around Portland's dates instead of trusting one.