The winter nor'easter set to make its way up the Mid-Atlantic coast on Saturday could result in potentially historic flooding at the Jersey Shore and Delaware beaches.
"The threat of coastal flooding has INCREASED," cautioned a late-afternoon National Weather Service briefing.
Forecasters are urging homeowners to begin planning now to take action to minimize the effects of what could become one of the five worst flooding events in Cape May and Lewes, Delaware going back to the 1940s.
Atlanta-based meteorologist Ryan Maue tweeted a map Tuesday afternoon showing atmosphere-wave models predicting 20 to 30-foot-plus waves in the open sea on Saturday off the South Jersey and Delmarva coast.
Open sea waves of that size translate into 12 to 15-foot waves on shore, said Gary Szatkowski, meteorologist with the National Weather Service in Mount Holly.
The storm will coincide Saturday night with the full moon, which combined with very strong winds, will cause major flooding along the New Jersey and Delaware coasts, according to Szatkowski. The flooding could be "close to Sandy" in terms of severity, he added.
While it would only take a 1.5-foot storm surge at the time of Saturday morning's high tide to see flooding, they say the storm very well could cause a 2-to-5-foot surge and significant waves. If that happens, the result would be extensive flooding that would cause damage in some areas, erode beaches and lead to road closures, forecasters warn.
Periods of heavy precipitation could add to the flooding.
The severity of the flooding will be determined by the direction of the wind at the time of high tide. If the winds blow northerly, flooding potential will be reduced. "If it's northeast and gusting to near 50 knots (57mph) along the nearest couple of miles of NJ and Delaware coasts, then we've got a big problem on our hands," the earlier discussion noted.
In the briefing, forecasters said moderate-to-major flooding is expected on the Delaware coast of the Delaware Bay, but no threat is seen along the Delaware River or Chesapeake Bay.
But it's too soon to know the exact severity of the flooding, forecasters cautioned.
