That’s why it’s not the evacuation that scares me. It’s largely unnecessary. The scary thing is the day – and the week – after the storm hits. Millions without power, or quite likely, potable water. Most major infrastructure disabled or destroyed. And since many of the most vulnerable areas are also among the most impoverished, a displaced population that may prove difficult to control. We saw chaos reign in New Orleans after the storm; New York City could be much worse. Those are my fears.

Of course, as the map says, “A major hurricane is unlikely in New York City, but not impossible.” I would add that, depending on the storm’s direction, a Cat. 2 might be effectively a Cat. 3 or 4, if its forward speed is fast enough (a la the 1938 Long Island Express, which was moving north at 60 mph, thus adding a whole tropical storm’s worth of punch to the right-front quadrant).

Admittedly, the particular angle of approach into NYC necessary to make that scenario happen is very unlikely… I would assume we’re talking about, like, a thousand-year storm, or something in that ballpark. Like Berger said: “low threat, high consequence.”

Maybe not the above-ground portions, but wouldn’t it flood substantial portions of the subways?

So it would be a disaster. And the southern part of Brooklyn, Lower Manhattan, and Staten Island, in particular, would be devastated. In fact, they’d be hit pretty hard by a hurricane of any size. But New York simply isn’t all that vulnerable to storm surge flooding, and that’s often the most devastating aspect of a hurricane. The real challenge, I suspect, won’t be evacuation, but rather, law enforcement. That’s what broke down so memorably during Katrina. NYC has an enormous police force, but it isn’t equal to this kind of challenge. Nor, for that matter, is the overstretched national guard. The hurricane would be bad; I suspect the aftermath would be even uglier.