Waves, currents, and tides threaten thousands of miles of American
trails (any within a quarter of a mile of a waterway), and hikers can get caught in the barrage. Headland-sculpting, beach-pounding waves can swallow an unwary trekker without so much as a burp. Learn how to recognize, negotiate, and avoid nearshore hazards
AVOID KILLER WAVES Prevent a surprise encounter with these giants.
>> Storm surges and swells winds and low atmospheric pressure can force water ashore, generating a surge, extreme high tides, and enormous swells that compound the danger of storm surf. Monitor weather-related tidal shifts pretrip by visiting NOAA’s National Hurricane Center website (nhc.noaa.gov) for surge predictions and inquire with rangers about hazardous areas. If a storm threatens, move to high ground; dangerous surf and tides may last several days. >> Rogue waves These giant swells are formed when waves collide and combine. The largest rarely hit coastlines, but there’s no way to predict when a monster will (and even moderately-sized surprise waves can knock you off your feet). Scan the surf as you hike and always be prepared to climb above sea level or hold onto a big rock as a last resort. >> Tsunamis Major undersea earthquakes can send a deadly wall of water surging ashore within minutes–or up to a day after an event on the other side of the globe. If you notice signs of seismic activity, like shifting sand, swaying trees, rockslides, or a sharply receding water level, don’t wait for an alert. Run or climb to between 50 and 100 feet above sea level and stay on high ground for at least 12 hours.