Sandy was an enormous storm, with a diameter of 700 to 1000 miles, and it struck the New Jersey Coast and New York metropolitan area with storm surge of 13 to 15 feet and winds gusting to 90 to 100 mph, notes Annes Haseemkunju, an Oakland, Calif.-based atmospheric scientist with EQECAT. "Flooding was huge, and somewhat unexpected because of the storm's arrival coinciding with astronomical high tides," he comments.
While the degree of flooding was unusual, Sandy was probably not a "storm of the century," insists Haseemkunju. "We've seen such damage-causing events in the past," he says. "We'll find out as more information comes in, but this was more like a 15- to 20-year event, or possibly even less."
Only last year, Hurricane Irene caused $6 billion insured damages and economic damages as high as $15 billion. Others events in recent years have been in that ballpark, and within the century there have been hurricanes with higher overall economic loss estimates when adjusted to 2012 dollars. A hurricane in 1903 may have been more destructive, though it is hard to estimate the kind of damage it might have done had it struck today. But more is known about other storms that have struck the Mid-Atlantic coast since then, according to Haseemkunju. He cites the following storms:
Irene, 2011: $10-$15 billion
Floyd, 1999: $3-$5 billion
Gloria, 1985: $7-10 billion
Hazel, 1954: $20-$35 billion
Long Island Express, 1938: $20-$30 billion
[For more catastrophe coverage, see Sandy Update: Flood Insurance Program Under Siege.]