'Wicked high tide:' Days of coastal flooding in Northeast not over yet

A coastal storm has been lurking off the East Coast of the United States for five days, contributing to persistent coastal flooding, rip currents and rough surf from North Carolina to Maine.

Boston Harbor rose to minor flooding stage at the National Weather Service (NWS) tidal gauge for each high tide between Thursday and Sunday afternoon. The peak on Saturday afternoon put local businesses and roads underwater, as videos showed.

A local environmental group in Boston, Stone Living Lab, posted signs in the water directing onlookers to its website, which said, "Wicked High Tides are back! These annual tides are 2-4 feet higher than normal and give us a window into how sea level rise will soon affect our daily lives."

An NWS tidal gauge on the Chesapeake Bay at Bishop's Head, Maryland, rose into major flooding stage Sunday, hitting 4.41 feet, tying the fifth-highest level at that location, recorded on Dec. 22, 2022. The station has records that date back to 2005.

Boston, MA - September 20: A waiter at Chart House uses a garbage bag to protect against floodwaters. (Photo by John Tlumacki/The Boston Globe via Getty Images)

"The storm off the New England coast brought persistent onshore winds along a large swath of the Eastern Seaboard, bringing dangerously large surf that resulted in extensive beach erosion in some areas, Brandon Buckingham, AccuWeather Regional Expert, explained.

Coastal flooding and beach erosion were exacerbated by high astronomical tide cycles, called "King Tides," following the full supermoon last week.

Similar risks will continue along area beaches from New England to the Outer Banks of North Carolina through midweek as an onshore flow persists.

Although the coastal storm has weakened and will continue to shift south over the next few days, gusty onshore winds will persist, and there can continue to be episodes of coastal flooding, especially at high tide.

As of Monday morning, a total of 16 National Weather Service tidal gauges were forecast to rise into moderate flooding conditions early this week.