Roseburg is less than 3 hours from Portland, unless you hit traffic. It took us 4 hours to get home, but we also took 15-20 min to go through a car wash along the way. Temperatures in Roseburg late July 2020 were mid-90s. But it was the same in Portland. It was just hot everywhere, it seemed. Unreasonable for the Pacific Northwest, in my opinion. We’re supposed to be cool!
I've been in a wheelchair for 30+ years. It poses some challenges for traveling. Maybe others can benefit from my experiences.