PDX already had a pretty significant UHI in place by the 1990s. It's maybe degraded a little bit further since then (thanks IKEA!) but not to a super dramatic degree.
Internal Democrat polling for swing states is not looking good for Biden, per a NYT reporter.
https://www.reddit.com/r/ezraklein/comments/1dttpiz/biden_plunges_in_swing_states_in_leaked/
I read somewhere that PDX is one of the more prolific UHI afflicted stations in the lower-48 since the 1990s. I’ll have to dig up that analysis but it was quite thorough IIRC.