Both, but it’s actually not quite as bad as I thought it was, especially for you. This is the peak day:
Dewpoints at that point appear to be near 70 across PA.
What it does, and has been doing for quite some time, is build a massive ridge with all-time type heat in the north central states (the EC agrees on that general pattern, though nowhere near as intense). This run, it propagates that ridge eastward so that’s why it’s worse for me than it is for you. Most runs, it doesn’t. Still, those 100s are awfully close.