2015 National Hurricane Preparedness Week
Storm Surge Hazard
We continue our coverage of the 2015 Hurricane Preparedness Week by looking at some of the hurricane hazards. In particular, we'll start by examining the greatest potential for loss of life related to a hurricane, the storm surge.
Simply put, it is a dome of water that is pushed toward the shore by the force of the winds swirling around the storm. The advancing water, combined with the normal tides, can increase the mean water level by 15 feet or more. The threat is increased if it combines with high tide. Along the Atlantic and Gulf coasts of the United States, the mean sea level is around 10 feet, so a storm surge above that level could cause catastrophic damage.
The Many Factors that Influence Storm Surge
- Central Pressure
- Storm Intensity
- Storm Forward Speed
- Angle of Approach to Coast
- Shape of the Coastline
- Width and Slope of Ocean Bottom
- Local Features
Download INTRODUCTION TO STORM SURGE (PDF) for more background information about storm surges and consult the following links for animations and other useful information. Be sure to watch the PSA video below as well.
- Storm Surge Overview
- Notable Storm Surge Events
- Storm Surge Risk Map for U.S. Coast
- Storm Surge Vulnerability Facts
- Coastal Inundation Toolkit
Hurricane track forecasting continues to improve, but the the average track error 48 hours prior to landfall for the Atlantic basin is still considerable. The 24-hour to 48-hour window is often critical for decision-making. It is important not to focus solely on one storm surge product within this window. Storm specific uncertainties are accounted for in the probabilistic storm surge (p-surge) product, while the *MOMs and *MEOWs provide a worst case storm surge estimate at a regional level. More
For those in danger areas, it is wise to plan in advance of hurricane season. Be sure you know areas that would be safe when a storm approaches. You should be able to get to these safe zones quickly so that you don't risk being trapped by road congestion.
Hurricanes usually provide advance warning. When local officials recommend evacuation, heed their warnings and put your plan into action. Structures can be replaced, but lives cannot.
We'll continue our Hurricane Preparedness Week coverage by looking at additional hazards next. Consult the NHC and other websites for additional information about storm surges.