My memory is fading (early onset?), but I can't recall a (potentially) longer-lived Major Atlantic hurricane than Sam., forecast to remain a Major until passing east of Bermuda over the weekend. Sam's Accumulated Cyclone Energy (ACE) is sure to be impressive- I don't know at what point the ACE stops accumulating (extra-tropical?), but the forecast suggest Sam will remain a strong extra-tropical hurricane for several days after the transition:
"Around day 5, global model fields suggest that Sam will be merging with a baroclinic zone and transition into a large and powerful extratropical cyclone over the north Atlantic."