Storm surge

A storm surge reflects the difference between the actual water level under the influence of a meteorological disturbance (storm tide) and the level which would have occurred in the absence of the meteorological disturbance (WMO, 2008, 2011, 2017).

A storm surge is the rise in seawater level caused solely by a storm. It is the abnormal rise in seawater level during a strom, measures as the height of the water above the normal predicted astronomical tide. The surge is caused primarily by a storm's winds pushing water onshore.

Storm surge should not be confused with storm tide. A storm tide is the water level that results from the combination of the storm surge and the normal (astronomical tide).

This rise in water level can cause extreme flooding in coastal areas, resulting from storm tides reaching up to 6 meters (20 feet) or more in some cases (NOAA, 2019b.) On top of a strom tide are pounding waves generated by the powerful winds. The area of seawater flooding may extend along the coast for over 100 km, with water pushing several kilometres inland if the land is low lying. The combined effects of the storm tide and surface waves can destroy buildings, wash away roads and run ships aground (Australian Government, 2020).

Examples of National Alerting Parameters include storm surge warning issued in Canada (Government of Canada, 2019) and an Advisory for storm surge watch/warning issued by the World Meteorological Organization (WMO, 2017).

Different symbols of hazards and disasters.

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Latest Storm surge additions in the Knowledge Base

Documents and publications

30 September 2008

Disaster response and risk management in the fisheries sector

This document gives an overview of FAO’s work with regard to natural and human-induced disasters in the fisheries and aquaculture sectors, together with the lessons learned and experience gained on how to improve disaster response, preparedness, and

Update

28 September 2008

Jamaica: Portmore vulnerable to natural hazards - MGD study

"Essentially, the purpose of the study is to reduce the vulnerability of Portmore to natural hazards" said Norman Harris, at the Mines and Geology Division.

Jamaica Observer, the

Documents and publications

21 September 2008

Rivermed

This game is part of a project elaborated by a Mediterranean network (Catalogna, Piemont, and Provence-Alpes-Côte d'Azur (PACA)) of educators in the field of natural hazard reduction. This network has produced a kit of pedagogical tools on floods

Documents and publications

21 September 2008

RINAMED - Risques naturels en Méditerranée

This game, based on the Rivermed game, but extended to the other natural hazards, is part of the RINAMED (Risques naturels en Méditerranée) programme operated by the Centre Méditerranéen de l'Environnement, has received the support of the European Union

Documents and publications

21 September 2008

Volunteers training book: cyclone preparedness programme

Training Book, published in an abstract version for the training of the volunteers of the cyclone preparedness program in preparedness activities. It covers subjects like analysis capacity and vulnerability, introduction to cyclones, warning signals and

Educational materials

21 September 2008

Earthquakes: how and why

This book for teenagers explains what is an earthquake, and the seismic risk, where it occurs, what is a tidal wave, can they be predicted. It also describes the seismicity of Italy and queries if buildings can be rendered safer. It also gives some tips

Educational materials

21 September 2008

Be ready, be safe

The activities in this brochure, to be carried out with teachers and/or parents, aim to get 12-13 years' old children prepared to act safely in emergencies and disasters. (UNEsCO)