Storm Surges – Vulnerability Assessment


Storm surge is a very complex phenomenon because it is sensitive to the slightest changes in storm intensity, forward speed, size (radius of maximum winds), angle of approach to the coast, central pressure (minimal contribution in comparison to the wind), and the shape and characteristics of coastal features such as bays and estuaries.

Other factors which can impact storm surge are the width and slope of the continental shelf. A shallow slope will potentially produce a greater storm surge than a steep shelf.[1]

General Factors that Impact Storm Surge

There are several factors that contribute to the amount of surge a given storm produces at a given location:[4]

  • Wind Intensity (higher winds speeds=increased storm surge)
  • Storm Central Pressure (little impact)
  • Storm Forward Speed (slower storms=higher and broader storm surge inland including bays and estuaries; faster storms=more storm surge along the open coast)
  • Storm Size (storm with large wind field=more storm surge; storm with small wind field=less storm surge)
  • Storm Angle of approach (perpendicular to coastline=more storm surge; parallel to coastline=less storm surge)
  • Width and slope of continental shelf (wide shelf/gentle slope=more storm surge with relatively small waves; narrow shelf/sharp slope=less storm surge with relatively big waves)
  • Local features (concavity of coastlines, bays, rivers, headlands, islands, etc.=greater storm surge impact)

Figure 1: The following graphic indicates how storm surge is impacted by local geographical features:[5]

Storm Surge Vulnerability Assessment Questions

To assess your vulnerability to the threat of a Storm Surge to your family and property, perform an assessment to determine if you have knowledge of, are prepared and/or have a plan by answering the following questions:

General All-Hazard Questions:

  • Have you determined the disaster risks in your locale and the hazards that accompany them?
  • Do you know the emergency warning signals and alert notifications used in your community?
  • Have you instructed family members how to shut off water, gas and electricity to your house?
  • Have you made the necessary property preparations to reduce the damage from the hazard?
  • Do you have a backup generator in case of a prolonged power failure?
  • Have you purchased insurance (property, health, life, and/or hazard type)?
  • Have you made the necessary financial arrangements in case of a sudden evacuation and power outage that shuts down local ATMs and banks?
  • have you organized important documents and records and stored them in a portable lock box or safe-deposit box?
  • Have you performed a home inventory video taping the contents stored them in a portable lock box or safe-deposit box?
  • Does your family have an established Emergency Communication Plan and evacuation plan in place and asked an out-of-state person to serve as the “family contact”?
  • Have you assembled a shelter-in-place Emergency Supplies Kit in case you have to shelter at home and you are without power?
  • Have you assembled a mobile Emergency Supplies Kit that can serve as a “grab and go” bag?
  • Are you or someone in your family trained in first aid and CPR?
  • Have you made they necessary preparations and arrangements for pets, seniors, and the disabled?
  • Have you familiarized yourself with the emergency plans of your family member’s employment building, school, day care center, or nursing home?

Hazard Specific Questions:

  • Have figured out if you live in an evacuation zone and which zone it is?
  • Have you checked your house and land for any potential dangers related to flooding and have you repaired it?
  • Have you asked your insurance agent about flood insurance?
  • Have you acquired or made sandbags and do you have a plan to prevent water from entering your home?
  • Have you stored important documents in an off-site location such as a bank safety deposit box or at least at a higher level in your house, protected from flood damage?

Storm Surge Property Risk Report

According to CoreLogic, a leading provider of consumer, financial and property information and business services, a 2013 Report estimates 4.2 million U.S. homes valued at an estimated $1.1 trillion at risk of hurricane storm-surge damage.[6]

The CoreLogic Storm Surge Report, issued annually, provides a breakdown of residential property risk along the Atlantic and Gulf coasts at five key geographic levels – national, regional, state, metro and ZIP code. The 2013 findings reflect a significant increase in both the number of total properties at risk, as well as total value.

Key highlights of the 2013 CoreLogic analysis include:[7]

  • There are more than 4.2 million residential properties exposed to storm-surge risk valued at roughly $1.1 trillion, with more than $658 billion of that risk concentrated in 10 major metro areas.
  • Florida tops the state rankings with nearly 1.5 million properties at risk and $386 billion in total potential exposure to damage.
  • Louisiana ranks second in total properties at risk with just over 411,000 homes in storm-surge zones. New York ranks second in total value of coastal properties exposed at nearly $135 billion.
  • At the local level, the New York metropolitan area, which encompasses northern New Jersey and Long Island as well, contains not only the highest number of homes at risk for potential storm-surge damage, but also the highest total value of residential property exposed, at more than $200 billion.



  1. NOAA – National Hurricane Center – Storm Surge Overview:
  2. National Hurricane Center – Storm Surge Frequently Asked Questions:
  3. Image Source: [Accessed August 19, 2013]
  4. NOAA – National Hurricane Center – Introduction to Storm Surge:
  5. Image Source: [Accessed August 19, 2017]
  6. CoreLogic – 2013 Storm Surge Report –
  7. CoreLogic – 2013 Storm Surge Report –