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A trip to the beach should be fun. Unfortunately, many people are injured or killed along our nation's beaches by hazards sneaker waves and log rolls. The National Weather Service can help ensure you leave the beach with good memories. NWS provide you the information you need to stay safe on beaches and in coastal areas and surf zones. A surf zone is defined as the area of water between the beach/shore and the first line of breaking waves. See our photos of dangerous waves.

+What are Sneaker Waves and Why are They Dangerous?

+How far up the beach can Sneaker Waves travel?

Some of these waves can wash more than 150 feet (45 meters) up the beach. Most driftwood is the remains of trees that have been washed into the ocean by waves, winds, floods, logging, or other natural means that are carried by ocean currents along the coast, and then washed ashore onto the beach by the action of waves or tides as driftwood. It only takes a few inches of water to lift or roll a log weighing hundreds of pounds. When a powerful ocean wave known as a sneaker wave surges up the beach it is powerful enough to roll or even lift these extremely heavy logs knocking those individuals on them off and pinning them under the log.

+Why are logs on the beach dangerous?

Logs on the beach are wet and extremely heavy and can weigh hundreds of pounds. Yet a single sneaker wave can lift and roll these logs further up the beach, as well as roll them back down the beach. Anyone standing, sitting, or kneeling on one of these debris logs can suddenly be thrown off the log when a wave hits it and penned underneath. Not only is the victim now penned under a heavy log with possible serious injuries, but they are in jeopardy of being drowned by incoming waves washing over them filling their lungs with water and sediment. It can take an extended period of time to move one of these very heavy logs off the victim. Log rolls have proven fatal. Never, never stand, sit or play on debris logs on the beach.

+What should people know before going to the beach to avoid being a victim of a Sneaker Wave or a log roll?

Individuals planning to visit the beaches of North California, Oregon, and Washington State should educate themselves about the naturally occurring hazards at these beaches. Study wave patterns, never stop watching and listening to the ocean. It can change suddenly. Sneaker waves can surge high up the beach without warning catching the inattentive individual off guard. Expect these waves to move with great speed farther up the beach than you think is safe. No place on the beach is too high for the wave to reach. Be aware of the following dangers:

  • The force and speed with which sneaker waves move
  • Their frigid temperature
  • The volume of sand, water, and gravel they carry and will deposit in an individual’s clothes. Survivors have described the water-sand mix in their clothes as feeling as heavy as concrete rendering them incapable of escaping the receding waves pulling them into the ocean.

Exposure to the cold water can cause cold water paralysis to set in in the limbs within minutes further impairing the individual’s ability to escape the wave. It's important to always have an escape route when you're on the beach, especially the steep, enclosed beaches of the Northwest.

+What makes the Northern California-Oregon-Washington coasts more dangerous than the Southern California coast?

The coastline of Northern California, Oregon and Washington State are steep, tree lined, and have cold to frigid water temperatures. These beaches are quite unlike the flat, broad beaches of Southern California with their inviting warm water temperatures. The steep slopes of the Northwest’s coastlines are much more likely to cause sneaker waves; the trees that line the cliffs can wind up in the swift ocean currents running along the shoreline; while the cold to frigid temperatures, depending on the season, can induce cold water paralysis for anyone caught in these northwestern ocean waters.

While in Southern California people at the beach are in bathing suits or light summer clothes wading and swimming in warm waters with open beaches, in contrast in the North they wear heavier clothes, coats, shoes, and boots due to the cooler temperatures and in autumn and winter those waters are frigid. Encounters with the waves in Southern California, with its warm water temperatures and broad beaches, might simply knock a person over on the beach, but in the North the cold water temperatures could induce cold water paralysis rendering the individual helpless to escape the pull of the receding wave returning to the ocean.

Always respect the ocean on the beaches of the North Coast of California, Oregon, Washington with their steep, rugged tree lined coasts, and frigid ocean temperatures.

+What should you do when first arriving at the beach?

  • Don’t make the beach your grave. Constantly watch the ocean for changes in wave patterns!
  • Expect and listen carefully for changes in the incoming waves. Do what experienced surfers and lifeguards do, watch the ocean for at least 20 minutes. Study its wave patterns. Get a feel for the pattern of the waves before relaxing on the beach or engaging in recreational activities.
  • Know the local forecast for the day. Look to see if there are statements regarding sneaker waves or other beach hazards.
  • Stay farther back from the ocean than you think is necessary. Sneaker waves can run up the beach by at least 150 feet (45 meters) into the dry beach.
  • Never stand on logs on the beach. Sneaker waves can run up on the beach lifting or rolling these extremely heavy water soaked logs on the beach. People have been injured and even crushed by being caught under these logs from sneaker wave action on the beach.

+What does a log roll look like: photos

  • Log roll debris from Oregon coast. Courtesy Tyree Wilde, NOAA. Click for full size image.

    Log roll debris on oregon shoreline, courtesy NOAA Log roll debris on oregon shoreline, courtesy NOAA Log roll debris on oregon shoreline, courtesy NOAA

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