Birds on the Brain

Forecast for Sandy

Wind shear is expected to remain a high 30 - 40 knots for the next two days, as Sandy interacts with a trough of low pressure to its west. The high shear should keep Sandy from intensifying the way most hurricanes do—by pulling heat energy out of the ocean. However, a trough of low pressure approaching from the west will inject “baroclinic” energy—the energy one can derive from the atmosphere when warm and cold air masses lie in close proximity to each other. Sandy’s drop in central pressure from 969 mb at 5 am to 960 mb at 8 am this morning may be due, in part, to some baroclinic energy helping intensify the storm. This sort of effect helps spread out the storm’s strong winds over a wider area of ocean; Sandy’s diameter of tropical storm-force winds are predicted to expand from 660 miles to 760 miles by Sunday afternoon. This will increase the total amount of wind energy of the storm, keeping the storm surge threat very high. This morning’s 9:30 am EDT H*Wind analysis from NOAA’s Hurricane Research Division put the destructive potential of Sandy’s winds at a modest 2.3 on a scale of 0 to 6, However, the destructive potential of the storm surge was exceptionally high: 5.2 on a scale of 0 to 6. Sandy’s large wind field will drive a damaging storm surge of 3 - 6 feet to the right of where the center makes landfall. These storm surge heights will be among the highest ever recorded along the affected coasts, and will have the potential to cause billions of dollars in damage. The latest set of 00Z (8 pm EDT) and 06Z (2 am EDT) computer model runs have come into better agreement on the timing and landfall location of Sandy. Our two top models, the ECMWF and GFS, both call for landfall between 10 pm Monday night and 4 am Tuesday morning, with the center coming ashore between Delaware and New York City.

A multi-billion dollar disaster likely in the U.S.

I expect Sandy’s impacts along the mid-Atlantic coast and New England coasts to cost at least $2 billion in insured damage and lost business, and there is a danger the storm could cost much more. Steve Bowen, meteorologist for insurance broker AON Benfield, put it this way for me this morning: “Given the level of losses associated with Irene last year and the current projections of extended high wind, heavy rainfall, coastal surge and an inland flooding threat for many of the same areas with Sandy, it would not come as a complete surprise to see a multi-billion dollar economic loss.” Sandy should bring sustained winds of 50 - 70 mph with gusts over hurricane force to a large section of coast. With most of the trees still in leaf, there will be widespread power outages due to downed trees, and the potential for a billion dollars in wind damage.

(via Dr. Jeff Masters’ WunderBlog : Sandy likely to be a multi-billion dollar disaster for the U.S. | Weather Underground)

Sandy has already killed 48 people, including 34 in Haiti and 11 in Cuba. This storm has potential to be worse than Irene in the Mid-Atlantic and Northeast.