The National Weather Service says powerful thunderstorms created a small weather generated tsunami off the southern New England and New Jersey coasts.
Known as a meteotsunami, it resulted in fluctuating water levels for several hours Tuesday. But there were no reports of damage from the event.
"Storms that moved across the area yesterday ended up creating a meteotsunami across the mid-Atlantic and up into the [southern New England] coastline," the service posted from its NWSBoston Twitter account. "You can see the meteotsunami in the water fluctuations from area tidal gauges, especially in the New Haven gauge."
Abnormally high tides were reported in areas from Perth Amboy in New Jersey to Delaware's Fenwick Island.
Officials say meteotsunamis are driven by air-pressure disturbances often associated with fast-moving weather events, such as severe thunderstorms, squalls, and other storm fronts. Most meteotsunamis are too small to notice.
The cleanup is underway throughout the northeast a day after powerful storms pounded the region with torrential rain and marble-sized hail, leaving at least three people dead and hundreds of thousands of customers without power.
Connecticut officials said a woman was killed Tuesday when a tree fell on her vehicle in New Fairfield, and in Danbury, a man who had taken refuge to escape the storm was killed when a tree fell on his truck. An 11-year-old New York girl was killed when a large tree toppled onto the car she was in.
The storms downed trees and power lines across the region. Several lightning strikes led to structure fires in New Jersey and Massachusetts. Roads in many towns were impassible and some schools canceled classes on Wednesday due to the damage.
Airlines also canceled and delayed flights in and out of the region.
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