Weather September 2025 Portland

Weather September 2025 Portland. The temperatures in portland in september are usually low and can range between 55°f and 68°f. Daily high temperatures decrease by 4°f, from 67°f to 62°f, rarely falling below 58°f or exceeding 72°f.

Fall 2025 is forecast to be warmer than average for most in the u.s. Free long range weather forecast for portland, oregon september 2025.