"Sandy is shaping up to be a historic storm for the mid-Atlantic and Northeast U.S. that has few precedents." - Dr. Jeff Masters
WeatherUnderground.com expert Dr. Jeff Masters says that if Sandy was to follow the America Model (GFS), that Manhattan could see its seawalls violated by the storm. The result would be flooded subways and tunnels. Glass could be blown out in the upper levels of skyscrapers and trees would be down everywhere.
The storm is no longer an 'if' about hitting the United States but where and when it hits. The Euro Model still has it coming ashore near Cape May, New Jersey. Rainfalls can be expected in certain areas of over 10+ inches. The storm surge could last through two high tides since the storm is moving so slow.
Here is Dr. Master's view on the severity of the impact:
"Sandy's expected landfall along the mid-Atlantic coast is likely to be a billion-dollar disaster. Sandy should bring sustained winds of 50 - 60 mph with gusts over hurricane force to a large section of coast, and the storm may be moving slowly enough that these conditions will persist for a full 24 hours. With most of the trees still in leaf, there will be widespread power outages due to downed trees. Sandy is expected to have tropical storm-force winds that extend out more than 400 miles from the center, which will drive a much larger storm surge than its winds would ordinarily suggest.
The latest H*Wind analysis from NOAA's Hurricane Research Division put the destructive potential of Sandy's winds at 2.1 on a scale of 0 to 6, and the destructive potential of the storm surge much higher, at 4.2 on a scale of 0 to 6. The full moon is on Monday, which means astronomical tides will be at their peak for the month, increasing potential storm surge flooding. With Sandy's strongest winds expected to last at least 12 hours near the time of landfall, the peak storm surge will affect the coast for at least one high tide cycle, and possibly two. This will greatly increase the potential for storm surge damage and coastal erosion.
If Sandy hits Long Island, as the GFS model predicts, the storm surge will be capable of over-topping the flood walls in Manhattan and flooding portions of the New York City subway system. Fresh water flooding from heavy rains is also a huge concern. Rainfall amounts of 5 - 10 inches will occur over several hundred mile-long swath of coast, with isolated amounts of 15 inches possible. Fortunately, soils are dry and river levels are low over most of the threatened region, which should keep Sandy's river flooding lower than that experienced last year during Hurricane Irene. Nevertheless, Sandy is shaping up to be a historic storm for the mid-Atlantic and Northeast U.S. that has few precedents."