Frankenstorm Exits
The storm devolved into a normal winter storm early this morning and the special reporting ceased. Now the emphasis is on the damage it caused, including the loss of life experienced along the Atlantic Coast. It is fairly certain that the name “Sandy” will be retired from the list of storm names.
I mentioned a discussion I was reading about making changes to the Saffir–Simpson scale, because it is based solely in the wind speed, and Sandy’s winds were never that high. There are a lot of local people wondering how this storm could cause that much damage.
The problem is that while people repeat the old truism that ‘it’s not the wind, it’s the water’ they still rate hurricanes based primarily on the wind speed.
What I saw looking at the numbers was a storm that would have been a Category 3 storm without the high wind shear it was fighting beginning in the Bahamas. It had the barometric pressure and surge associated with Category 3 storm, but the winds of a Category 1 when it approached landfall in New Jersey.
I rarely mentioned fact is that sea level changes based on the barometric pressure. Normal sea level occurs at the normal pressure of 1013.25 millibars. For every millibar of drop below that point, sea level rises a centimeter. Sandy went ashore with a pressure of 940 millibars. it was on a mound of water that 73 centimeters [28.74 inches] above normal sea level. You add the rising tide, and the water being pushed by the winds, the effects are devastating.
We build for the water down here. The first floors on all of the newer buildings on our barrier island are either open parking areas, or designed with break-away walls front and rear, so that when the surge hits it flows through the first floor without knocking the building off its foundation.
We obviously need to find a new way of rating hurricanes to deal with the huge wind field, low pressure storms like Sandy, because people don’t seem to understand what the guys at the National Weather Service were yelling about when they figured out where this storm was heading.
This storm was bad news from start to finish. The Cubans have one of the best hurricane response plans around, and they were amazed at the damage that Sandy caused when it passed over Eastern Cuba as a small Category 2 storm. My concern is that Sandy may be the new ‘normal’.