We’ve come to expect a lot from Florida weather.
Sweltering heat — sure. Severe thunderstorms — been there, done that. Meteotsunami — I’m sorry, what?
That’s right, a meteotsunami. Last week the weather phenomenon formed on Clearwater Beach as a line of severe weather rolled in from the west. Water levels rose about 2 ½ feet higher than what would have been normally expected, according to water level data.
While the term may be unfamiliar, it’s not uncommon for our area. Just a week prior, a meteotsunami also occurred on Clearwater Beach.
What is a meteotsunami?
A meteotsunami produces a similar wave to a tsunami, however the cause of this wave is different. Seismic activity causes a tsunami, while a meteotsunami is caused by weather (meteorology, get it?). A disturbance in air pressure often coupled with fast-moving severe storms can produce these waves, according to the National Oceanic and Atmospheric Administration.
“The storm generates a wave that moves toward the shore, and is amplified by a shallow continental shelf and inlet, bay or other coastal feature,” the administration said.
The meteotsunami on Clearwater Beach occurred just before 2 p.m. Wednesday as storms marched toward shore. Preliminary data from the National Oceanic and Atmospheric Administration shows water levels peaked at about 5 ½ feet.
“A lot of times when that happens — you get squall lines like that or there’s a big cluster of storms that come in — they produce so much wind that you end up with a little push of a foot or two ... of extra water on top of the tide briefly,” said Paul Close, a senior meteorologist at the National Weather Service’s Tampa Bay office.
How common is a meteotsunami?
They happen more often than you think. Close said he noticed a meteotsunami a week prior on June 17 on Clearwater Beach, the same day a waterspout cropped up injuring two people. Preliminary water level data shows the tide peaking at about 5 feet, about 2 feet above the anticipated water level that day.
A meteotsunami can happen when a line of storms (not just a single storm) rolls in from the west, Close said. However, storms forming in the west are unusual for our area. An average summer afternoon thunderstorm, which often start to the east, won’t produce a meteotsunami, he said.
Conditions for a meteotsunami are most favorable along the East Coast, Gulf of Mexico and the Great Lakes, according to the National Weather Service.
Research from the National Oceanic and Atmospheric Administration suggests about 25 meteotsunami occur along the East Coast a year. A vast majority are small, meaning less than a foot and a half.
How dangerous are these waves?
Damage from the meteotsunami Wednesday was isolated to some flooding on the beach, according to photos Close saw.
Waves can be higher in other areas of the world. Meteotsunamis have been recorded to reach heights of 6 feet or more, the administration said.
In 1992, for instance, Daytona Beach recorded a 10-foot meteotsunami that crashed onto shore, injuring 75 people and damaging 100 cars, according to the weather service.
Close said regardless of whether a meteotsunami is headed your way or not, you shouldn’t be on the beach during a storm anyway. Gusty winds and lightning pose serious threats. And let’s not forget about waterspouts.
When the sky darkens and you hear rumblings of thunder, Close said, it’s time to hightail it off the beach and seek cover.