Preword: The title 'Sandy Repeat' refers to a similar way to how Sandy formed, NOT the strength or effects.
The ECMWF model is printing out a scenario all too familiar for those who went through Superstorm Sandy. Please take a look below.
Now, if this even happens (which there is no for-sure indication it will), it will probably not be as bad as Sandy. Sandy was a Category 1 hurricane just before landfall. This system looks like it would be a Category 1 hurricane at maximum- it will be weaker than Sandy. Also, the ONshore system would likely be weaker than the Arctic one that merged with Sandy, meaning that the possible new, combined system would be weaker than Superstorm Sandy.
However, keep in mind that the ECMWF kept on the right track of Sandy while other models incorrectly took it out to sea. Considering the ECMWF has been showing this Sandy-repeat system for at least two model runs, this is definitely something to watch.
I am not making a call yet, I want to see how the other models react to the ECMWF. Right now, the GFS is not in favor of this solution, so just keep an eye out. This is the wait-and-see mode, not PANIC-RIGHT-NOW mode.