August 24, 2011 – Hurricane Irene Continues on its Catastrophic Course: Irene is currently a rapidly strengthening, category 3 hurricane heading for the eastern seaboard (see map). We still don’t know exactly where or when it will strike land, but we do know that the potential impact could be catastrophic. A major hurricane hitting the East Coast, with sustained winds of 100 miles per hour or higher, has long been considered an economic worst-case scenario.
According to the latest computer forecast models, here are the three most likely outcomes:
(1) Irene takes an interior track, passing near Raleigh, N.C., Richmond, Va., Washington, D.C., Baltimore, Md., Philadelphia and New York City. This is by far the worst case scenario. Winds of up to 100 mph would scream past the Capitol in Washington, D.C. The streets of Philadelphia could be flooded with two feet of rain. Storm surge could raise the level of New York Harbor by 10 to 15 feet, inundating whole neighborhoods, filling the subways with saltwater, and knocking out power and communications to Wall Street.
The latest models are showing a decreasing likelihood that outcome #1 will happen, although it’s still possible. That is because hurricanes spin counter-clockwise; the right-front section of the storm always has the strongest winds and worst weather. A storm like that would be catastrophic for many of the major cities along the east coast of the U.S. taking direct hits, because that would be on the right or east side of the storm.
(2) Irene skirts the Outer Banks of North Carolina as a monster storm and makes final landfall somewhere from New Jersey to New England (best guess is Long island, NY). Consensus seems to be gaining that this is the most likely scenario. Irene will weaken as it moves northward. However, because Irene will spend more time over the bathtub-like warm water of the Gulf Stream in this scenario, it will likely retain Category 1 or 2 strength when it makes landfall in the Northeast.
(3) Irene continues to shift eastward and misses the coast entirely, as happened with Hurricane Earl last year. We’ll get quite a scare, but all for naught. This scenario is fairly unlikely at this point and here’s why: The difference between this year and last year all centers on a westward shift of the persistent steering pattern known as the Bermuda high. That high-pressure system is stronger this year and therefore, more likely to push storms westward toward land.
Regardless of Irene’s exact path, many coastal areas from North Carolina to New England are expected to receive 10 to 15 inches of rain over the coming days.
Remember, all this remains in flux. This past weekend, Irene seemed destined for Miami, with a repeat of Hurricane Andrew on Floridians’ minds. Tuesday, the forecast track shifted north and east to the Carolinas as Irene lingered north of the Dominican Republic. Last night, New York City was on the forecast track as Irene shifted further east. This morning, weather models have shown a continued creep eastward, but at a slower pace.
The latest run of the storm track model, based at Princeton University, shows Irene digging even further west, fitting more of the first worst-case scenario outlined above in outcome #1.
The Master of Disaster