I've lived in both cities, Austin for four years in the mid-80's and Portland since 1987. I much prefer Portland. You can always layer up in a cool climate, but the summer heat and especially the humidity in Austin is unbearably uncomfortable to me. Everyone just goes from one air conditioned space to another from May to September. Portland has wonderful dry warm summers, and the total rainfall in both cities is comparable although the rainfall patterns are quite different. Oregon also has a lot more going for it in the way of public land recreation opportunities within easy driving distance, you need to go all the way to Colorado or New Mexico from Austin if you want to go for a hike, ride or skiing in the mountains, and the Pacific Coast beats the Gulf Coast hands down. Seattle and Vancouver BC are also an easy day's drive from Portland, and much nicer than Dallas, Houston or San Antonio. It used to be the music scene in Austin was the city's main selling point; it still exists but Portland has an outstanding music scene of its own, not to mention too many microbreweries to keep track of and an amazing number of world-class restaurants. Did I mention the bugs, rednecks, and dry counties in Texas?

btw, summer doesn't start in portland until after July 4.