A neat weather phenomenon unfolded yesterday as a potent line of thunderstorms (the same squall line that officially reached derecho criteria over the Ohio Valley) pushed off the Jersey Shore.
What’s known as a “meteotsunami” (similar to a seiche) may have impacted the south coastal waters of Long Island and New England.
Meteotsunamis are not unheard of, they show up on tide charts every few years on the East Coast when the right weather factors come together.
In this case, the large, powerful squall line moving offshore – and its associated strong wind field and small pressure drop – was enough to cause the undulations/waves necessary for the phenomenon.
Below are 4 RADAR screen shots from Thursday morning through early afternoon, followed by a series of Tide Charts. Note the small “hiccup” in the bell curve that occured yesterday afternoon as the strong mesoscale convective system passed south of New England.
Tide charts from waters in Eastern New England (Boston, for example) don’t show the same feature as those waters were protected from the event. Likewise, waters inside of Long Island Sound didn’t register the “tsunami” nearly as much.
Credit to USGS staff and video from a Falmouth town official documenting this!!