On a long-term basis, we don't know if it's normal for successive cat5 hurricanes, or even converging, simultaneous multiple hurricanes. Over time, we simply have NO reliable long-term data upon which to say what it is that describes normal hurricane activity. We only have knowledge of what has been said over the last 600 years.
True, Pielke normalized for that and found that the most expensive hurricane remains Miami 1925 (or some year close to that).