Anatomy of a hurricane storm surge

AUSTIN (KXAN) - Out of all of the hazards a hurricane presents, storm surge is actually the most damaging and the most dangerous.

Let’s start by explaining what exactly storm surge is.

Storm surge is a rise in the sea surface, created when a hurricane’s wind blows over a large distance of ocean water. This wind effectively piles the water up along the shore.

Since winds in a hurricane circulate counter-clockwise, the area on the right side of a storm hitting the Gulf Coast gets the worst storm surge.

• Tracking Isaac's path

Another thing to consider is that storm surge does not take into account waves or tides.

With Isaac, we’re expecting a storm surge of 9-12 feet. Add that on to a high tide of 1-2 feet and waves of up to 10 feet, and we’re looking at the potential for the water surrounding New Orleans to be 20-24 feet higher than usual.

The new levee system – an investment by the US Army Corps of Engineers of over $14 billion – was designed to withstand a category 3 storm. With Isaac only at category 1 status, you would think that means New Orleans is in the clear.

But Isaac’s slow movement and large wind field, combined with the fact that New Orleans is on the right side of the storm, makes this hurricane a little more dangerous than the average category 1. The large wind field from Hurricane Isaac will pile up massive amounts of water from the Gulf of Mexico into Lake Pontchartrain and the New Orleans area, in what will undoubtedly be a nail-biting test of the beefed-up levee and pump system.

David Yeomans earned his Master's of Science from the University of Miami specializing in hurricane research. He was a guest scientist aboard the NOAA Hurricane Hunter aircraft.