Hurricane Earl

Pre-Landfall 5 | Summary
Posting Date: September 2, 2010, 4:45:00 PM

In the hours since this morning's 8 am National Hurricane Center (NHC) advisory, the central forecast track for Hurricane Earl has shifted slightly to the east and further from North Carolina's Outer Banks. The storm has also undergone some weakening and is now a Category 3 hurricane on the Saffir Simpson Wind Scale with maximum sustained winds of 125 mph. Although further gradual weakening is expected, Earl should maintain its status as a major hurricane (Category 3 or higher) as it passes the Outer Banks. The center of Earl is currently located about 245 miles south of Cape Hatteras and is moving due north at 18 mph. Earl took the northward turn that had been expected, but did so somewhat earlier than projected. The result is that Earl is now expected to bypass the Outer Banks at a distance of about 70 miles to the east. According to the NHC, there is currently about a 30% probability that North Carolina’s barrier islands will experience hurricane force winds. Even in the absence of hurricane force winds, however, strong gusts and a storm surge of 2-3 feet above high tide remain a concern. North Carolina has also retreated somewhat from its previously very stringent wind-borne debris zone, which has implications for potential damage to glazing. In addition to the evacuations issued for Hatteras and Ocracoke Islands yesterday, Currituck and Dare counties in the Outer Banks have now also issued mandatory evacuation orders. While the slight shift in forecast track takes Earl slightly farther from North Carolina, it takes the storm closer to Massachusetts' Cape Cod and the islands of Nantucket and Martha’s Vineyard; the central track in the NHC’s cone of uncertainty would now take the center just 15 miles east of Nantucket and 30 miles east of Cape Cod—likely as a Category 2 hurricane. It should be emphasized, however, that even a slight shift to the left or right can have a major impact on losses. Should Earl take the left-most track within the NHC’s current cone of uncertainty—a near worst case scenario—the center could pass just off easternmost Long Island, track through Rhode Island and into heavily populated eastern Massachusetts. The NHC estimates its forecast uncertainty cone using historical track data; specifically, the cone is defined such that 60-70% of historical tracks will remain within the cone given a starting location.

Pre-Landfall 5 | Downloads
Posting Date: September 2, 2010, 4:45:00 PM