Last week, when a line of thunderstorms moved across Clearwater Beach, Florida, located just west of Tampa, it unleashed gusty winds, torrential rain and another unique weather phenomenon that sent beach chairs tumbling.
According to forecasters at the National Weather Service (NWS), the culprit of the disturbance at Clearwater Beach last Wednesday was a type of tsunami. Rather than the one caused by earthquakes, this type of tsunami – known as a meteotsunami – was triggered by gusty thunderstorms.
Meteotsunamis have similar characteristics to earthquake-generated tsunamis, but they are caused by air pressure disturbances, which can often be associated with intense, fast-moving storms. A shallow continental shelf, inlet or bay can amplify a storm-generated wave.
As soon as the storm’s leading edge passes onto land, meteotsunamis typically subside. Generally, the entire ordeal only lasts about an hour.
But during that time, the wall of water can create sustainable damage along the coastline.
Last Wednesday, a line of potent thunderstorms tracked inland across Clearwater Beach from the Gulf of Mexico around 1:45 p.m. EDT, according to WTSP. The combination of the shallow slope off the coastline and wind gusts up to 40 mph led to this weather event.
Water levels at Clearwater Beach surged 2.5 feet higher than average, according to AccuWeather Social Media Producer and Meteorologist Jesse Ferrell.
A photo shared on Twitter showed beach chairs that were dragged into the water after the wave had passed. No injuries or water rescues were needed.
While the term meteotsunami may be unfamiliar to some, these events aren’t common, but they are not unheard of in different parts of the world.
“In the United States, conditions for destructive meteotsunamis are most favorable along the East coast, Gulf of Mexico, and in the Great Lakes, where they may pose a greater threat than earthquake-generated tsunamis,” the NWS said.
The phenomenon has been reported in the Mediterranean Sea, the Adriatic Sea and off the coast of Australia.
One of the largest meteotsunamis events on record in the U.S. occurred in Boothbay Harbor in Maine in 2008. The harbor flooded and emptied out three times over the course of 15 minutes, and waves up to 12 feet (3.66 m) were recorded. Several boats and other key infrastructure were damaged in the harbor.
In 2013, a meteotsunami crashed along the New Jersey coastline. Three people were injured after the 6-foot wave swept them off a jetty and into the water, according to the NWS. The agency confirmed it was a meteotsunami due to the proximity of a severe weather pattern and the lack of a detected earthquake.
These events can be challenging to predict and range from small, almost undetectable waves of water to larger waves that can completely inundate coastal areas.
Produced in association with AccuWeather