Had several above 5 in the past couple weeks. Guess the pressure just let go.
So far it looks like only one data buoy is event mode and that one is in the Gulf of Mexico. It's not uncommon for very distant buoys to go into event mode as the seismic ripple races around the planet from these really big ones. They're meant to spot and warn of tsunamis, but do an interesting job of mapping ripples when a bunch of them go off.