Seems like a simple load balance issue. Having more generation than can be absorb by the grid can cause a cascade pretty easy. Some sub-grids got too much and some too little. In either case there are trips. This really does not seem to be a big deal unless you are in traffic in Dade County with millions of Juan Pablo Montoya types. But it is never considered safe to drive in Dade.
This hasn’t just affected Dade. There are sporadic outages throughout the state.