A storm surge is an offshore rise of water associated with low pressure weather systems like hurricanes. Storm surge is caused primarily by high winds pushing on the ocean's surface. The wind causes the water to pile up higher than the ordinary sea level. Low pressure at the center of a weather system also has a small secondary effect, as can the bathymetry of the body of water. It is this combined effect of low pressure and persistent wind over a shallow water body which is the most common cause of storm surge flooding problems. The term "storm surge" in casual (non-scientific) use is storm tide; that is, it refers to the rise of water associated with the storm, plus tide, wave run-up, and freshwater flooding.
Nine out of ten people (90%) who die in hurricanes in the United States have historically been killed by storm surges.
In the Pensacola area, storm surge has been especially devastating to beach communities on the barrier islands, like Pensacola Beach, Navarre Beach and Perdido Key, which can be completely covered in surge water in only a Category 3 hurricane.
- National Hurricane Center. The Deadliest Atlantic Tropical Cyclones, 1492-1996. Retrieved on 2007-04-14.