The 2006 Atlantic hurricane season started last week, as we all know by now. Since reading Aaron Naparstek's Big One last year and following what happened after Hurricanes Katrina and Rita and the rest of the 2005's hurricane-season-on-steroids, I've been pondering the possibility of a hurricane hitting town. After all, New York City is adjacent to the very same Atlantic Ocean as Hurricane Alley. An Inconvenient Truth portends future devastating hurricane seasons like 2005 as high sea surface temperatures continue to rise. Could New York City get hit by a Katrina?

Possibly, but unlikely. As I see it, there are two factors that keep New York relatively safe.

1) The Prevailing Westerlies
One reason that the Pacific Northwest has the cleanest air in the country is that the Prevailing Westerlies, the winds that, north of 35o north latitude, tend to blow out of the west. In Oregon and Washington State, these winds blow in from the vast Pacific Ocean, carrying air that has with no trace of pollution. But here in New York, the Westerlies carry all the emissions from midwestern power plants and other sources of pollution across the American continent right over us. But the Westerlies also steer hurricanes away from us. The typical track of a hurricane is to be carried toward the northwest by the Trade Winds in the tropics. But by the time a hurricane gets to the Horse Latitudes, between 30o and 35o degrees north latitude, it will gradually veer toward a track that takes it north and east (i.e., away from land). Here's an image of the track for 2000's Hurricane Isaac, a category 4 storm that I think illustrates as close to a "normal" track as possible for an Atlantic storm.

Of course, it is not impossible that a storm could hit New York, but the Westerlies make it unlikely, because by the time a hurricane gets as far north as New York City, it should be embedded in the Westerlies pushing it out to sea. So the Prevailing Westerlies send us impure air but also steer hurricanes away: If we have a love/hate relationship with them, it's easy to understand why.

2) Low Sea Surface Temperatures
Hurricanes need sea surface temperatures in the low 80's Fahrenheit to gain strength. Luckily, our seas are cold and cloudy and not amenable to Hurricane strengthening. I've put together a page that displays charts produced by three NOAA buoys that track sea surface temperatures in the waters off New York City. (Unfortunatley the most southerly of the three got pulled from its mooring. It was retreived, but it hasn't been put back on line yet.) As of this writing, our waters are in the 60s, so it looks like we're in the clear for the moment. These are the kind of temperatures that cause people to avoid swimming, but also weaken hurricanes: another mixed blessing.

- Sea Surface Temperatures in the Waters Off New York City [NOAA via S&F]