A storm surge, quite often, is the most dangerous part of a hurricane. Often it is the most damaging to property and the largest threat to life, according to the National Hurricane Center. During Hurricane Katrina, over 1500 were killed, many as a result of storm surges.
A storm surge is an unusual rise of water due to a storm. This is different from storm tide which is a rise in water level from a combination of storm surge and astrological tide. A storm surge is the water rise above the astrological tides. When a surge appears there can be severe coastal flooding, especially when it occurs during the normal high tide.
Storm surges happen when water is pushed, by the wind, onto the shore. This wind is moving cyclonically around the storm. The damage from the water being forced onto land creates a bigger impact than the storm itself.
There are different factors that help determine the potential damage from a surge. The smallest change in storm intensity can alter it as can the speed a storm is moving, its size measured by radius of maximum winds (RMW), the angle that the storm is approaching the shore, central pressure, the shape and the characteristics of the coast are all factors that affect a surge.
If the continental shelf in an area is shallow, a storm surge has the potential to be greater than if the continental shelf is steep. Areas such as Tampa Bay, Florida or Galveston, Texas have shallow continental shelves. This means if a large storm surge hit these areas, the water from the surge could cover roads, cars, homes, animals, buildings and people. When the water recedes, homes, businesses, coastal areas and beaches would all wash away.
To prepare for a storm surge, it is important to listen for weather warnings in the area. In case of potential power outages, a battery-operated radio should be used.
People should also be prepared to turn off electricity and gas to the home. Know how to do this in case local officials tell residences to do so.
It is also wise to have a home emergency kit prepared at all times. This kit should include, but not be limited to, a first aid kit, flashlights, batteries and drinkable water. It is also good to know where all a person’s important documents are located in case an evacuation is ordered. If an evacuation is in effect, it is dangerous to remain in the area.
The Saffir-Simpson Hurricane Scale, which predicts possible damage due to wind levels, is not an indicator of potential damage from storm surges. To help the possible danger of people becoming confused about what to do, some emergency officials have begun to use the slogan “run from the water, hide from the wind,” as a rallying cry to warn people during a storm.