Unfortunately the slow and steady angle of approach is pretty much a worst case scenario from a flooding perspective. The core has only clipped the higher terrain, it is not weakening. But it's driving the southerly feed of moisture off the Carribean right over the island, with orographic enhancement. Maria was horrible and I don't want to say Fiona will eclipse that in impacts. But it may outperform even Georges from a flooding event. This is looking really bad.
Yeah, this is about the worst case rainfall scenario for PR. The videos coming out are already really bad.