High surf advisory: issued by coastal and oceanic meteorological agencies when powerful swells threaten populations and properties | Photo: Shutterstock

A high surf advisory is a warning issued by national weather services to warn coastal communities and beachgoers that large ocean waves and dangerous swimming and surf conditions are expected.

The criteria may vary by region and country, but it is only announced when it poses a threat to the population and public and private property.

Here are the key points you should know about high surf warnings:

  • They are usually issued for waves over eight feet (2.4 meters);
  • They indicate potentially hazardous conditions for swimming and surfing;
  • They tell the presence of strong rip currents that make it difficult to swim back to shore;
  • They warn about potential coastal flooding in some areas;
  • They inform about possible damage to coastal structures and infrastructure;
  • They let beachgoers know that they should exercise caution, pay attention to posted warnings, and follow the advice of lifeguards;
  • They advise communities to check the local forecast and conditions before heading to the beach;

When Is It Issued?

A high surf advisory is generally issued when ocean waves are expected to reach eight feet or higher.

Extreme ocean conditions can be due to several meteorological factors, such as strong winds, low-pressure systems, and storm surges.

The advisory is typically issued before the hazardous conditions so beachgoers can make informed decisions about their safety.

It is essential to check the weather forecast and conditions before heading to the beach, especially when a high surf advisory is in effect.

Storms: huge swells normally activate high surf advisories and warnings | Photo: Desipris/Creative Commons

Who Is Affected?

It affects anyone who plans to engage in activities near the ocean, such as swimming, surfing, fishing, or boating.

It is particularly relevant to beachgoers planning to spend time in the water, as large waves can create dangerous conditions that make it difficult to swim back to shore.

An official warning may also impact people near the coast, as it can cause coastal flooding and damage coastal infrastructures.

A high surf advisory generally affects anyone exposed to the ocean and its hazards when the warning is in effect.

So, stay informed and follow any advised safety precautions.

Should Surfers Follow the High Surf Advisory?

Yes, surfers are included in the people affected by a high surf advisory.

The large waves and strong currents can pose significant risks to surfers, making it vital for them to exercise caution and follow any advised safety guidelines.

Surfers should check the local weather forecast and conditions before heading to the beach and should be aware of any high surf warnings that may be in effect.

They may need to adjust their surfing plans based on the conditions and should follow the advice of lifeguards and other beach safety personnel.

High surf warning: when it is issued, people must stay away from the beach and shoreline | Photo: Shutterstock

How Can People Know a Warning Has Been Issued?

People can know about a high surf advisory through various sources:

  • Local news media: Television and radio stations often report on high surf advisories and other weather warnings;
  • Online weather resources: Websites such as the National Weather Service (NWS) or local weather portals provide up-to-date information on extreme coastal events;
  • Social media: Some weather services and local authorities use social media platforms to communicate warnings, including high surf advisories, to a large audience;
  • Emergency alert systems: Local and national emergency alert systems, such as the Emergency Alert System (EAS), can broadcast high surf advisory alerts through television, radio, and compatible mobile devices;
  • Beach signage: Local authorities may post high surf warnings on signs at the beach;

It is important to stay informed to stay safe and make informed decisions about water activities.

What Should People Do?

During a high surf advisory, people should take the following precautions:

  1. Avoid swimming in the ocean: Large waves and strong currents pose significant risks to swimmers;

  2. Follow the advice of lifeguards: Lifeguards are trained to monitor conditions and advise beachgoers on the safest ways to enjoy the beach;

  3. Stay alert: Pay attention to posted warnings and the advice of lifeguards and other beach safety professionals;

  4. Stay on dry land: It's best to stay on dry land and far away from the beach;

  5. Keep an eye on children: Children should be supervised at all times near the water and should never be allowed to swim in the ocean;

  6. Avoid rocky shorelines: Large waves can crash against rocky shorelines and cause significant injury;

  7. Check local weather and conditions regularly: Stay informed about the latest weather forecasts and conditions, and be prepared to adjust your plans based on the shifting circumstances;

Groundswells: high-energy wave trains often trigger coastal warnings | Photo: Bilcliff/Creative Commons

When Is the High Surf Advisory Canceled?

A high surf advisory is canceled by the National Weather Service when the hazardous conditions posed by large waves have subsided.

The exact timing of the cancelation of the advisory will depend on the specific meteorological conditions.

Still, typically, it is dropped when wave heights have decreased significantly and no longer pose a relevant threat to the population.

Ensure that you follow any advised safety precautions, even after a high surf advisory has been suspended.

Beachgoers should continue to exercise caution and pay attention to posted warnings and the advice of lifeguards.

How Long Can It Last?

The length of a high surf advisory will vary depending on the meteorological variables causing large swells.

Some high surf advisories may last only a few hours, while others may last for several days.

For instance, the National Weather Service (NWS) continuously monitors the conditions and updates the advisory as necessary.

Information is power, especially throughout the duration of a coastal warning event.

Beachgoers should check for updates and be prepared to adjust their plans based on the changing conditions.

Staying safe near the water is always a priority.

A Global Warning

High surf advisories are issued by coastal and oceanic meteorological agencies from all around the world.

The NWS issues high surf advisories in the United States to warn of hazardous conditions due to large swells.

Also, it distinguishes between a high surf advisory and a high surf warning - the former represents a "threat," and the latter represents an "especially heightened threat" to people and property.

Other countries with coastal regions, such as Australia, Canada, the United Kingdom, and New Zealand, have similar agencies that issue warnings for hazardous coastal conditions.

The terminology used for high surf advisories may vary from country to country.

Nevertheless, the basic concept is the same: to warn beachgoers and coastal residents about potentially dangerous conditions near the shore.

Here are some of the national governmental organizations responsible for issuing extreme coast event warnings:

  • Australia: Bureau of Meteorology;
  • Brazil: Instituto Nacional de Meteorologia;
  • Canada: Environment and Climate Change Canada;
  • Costa Rica: Instituto Meteorológico Nacional;
  • France: Méteo-France;
  • Ireland: Met Éireann;
  • Mexico: Servicio Meteorológico Nacional;
  • New Zealand: MetService;
  • Portugal: Instituto Português do Mar e da Atmosfera;
  • South Africa: South African Weather Service;
  • Spain: Agencia Estatal de Meteorología;
  • United Kingdom: Met Office;
  • United States: National Weather Service;

Top Stories

The most successful competitive surfer of all time, Kelly Slater, rode what may have been the last heat of his 24-year professional career.

Big wave surfing is an industry with an industry.

Jack Robinson and Gabriela Bryan have taken out the 2024 Margaret River Pro.

Ryan Crosby is the new chief executive officer (CEO) of the World Surf League (WSL).