DID YOU KNOW: 2012 derecho caused rare meteotsunami

The pressure difference and wind from the derecho changed water levels rapidly off parts of the East Coast

Storm damage left behind by the derecho in 2012

ROANOKE, Va. – If you’ve made it this far, you’re probably thinking two things. “What is a derecho?” and “What is a meteotsunami?”

1. A derecho is a widespread windstorm. The one in 2012 was a benchmark storm for our area.

2. A meteotsunami is a large wave that’s triggered by strong thunderstorms, such as derechos, squall lines, etc.

There are so many things we remember about the derecho of 2012, but the meteotsunami isn’t one of them. The reason is - it happened in parts of the Potomac and the Chesapeake Bay.

Derecho of 2012 caused rare meteotsunami off parts of the East Coast

Mike Montefusco, a lead forecaster at the National Weather Service in Wakefield, compares it to the bathtub effect where, “That water is being displaced by that wind coming out of a thunderstorm and changing the water levels.”

According to the National Oceanic and Atmospheric Administration, meteotsunamis happen most often in the Great Lakes and off the East and Gulf Coasts. Even still, they usually only happen once every ten years.

He recalls, “We actually saw water levels rise between half a foot to a little over a foot in the Chesapeake Bay and numerous ports.”

We asked Montefusco if something like that could happen on area lakes. He tells us that water levels can change any time a severe thunderstorm moves through, but that meteotsunamis are longer in duration.

If severe thunderstorm warnings are issued while you’re out on our area lakes, get to a safe spot quickly. Make sure you’re in the know while out and about by downloading our weather app.


About the Author:

Meteorologist Chris Michaels is an American Meteorological Society (AMS) Certified Broadcaster, forecasting weather conditions in southwest Virginia on WSLS 10 News from 5 a.m. to 7 a.m. weekdays on Virginia Today.