King Tide, Supermoon increasing flood risk from Outer Banks to Florida

Millions of people in the Southeast and mid-Atlantic are bracing for the threat of continued coastal flooding as seasonal King Tides, this month’s Supermoon, and relentless onshore winds combine to send water rushing inland into coastal communities.

This latest King Tide event occurs after nearly a dozen homes along North Carolina’s Outer Banks collapsed into the Atlantic Ocean due to massive waves that were kicked up due to hurricanes Imelda and Humberto last week.

This current King Tide is expected to bring another round of high water, with persistent onshore winds adding to the risk by trapping water along the coast, especially in Florida.

The King Tide coincides with the Moon’s closest approach to Earth, creating a Supermoon known as the Hunter’s Moon, or Harvest Moon.

The natural satellite’s gravitational pull causes the oceans to bulge on the side closest to the Moon and the side farthest from it, creating the two daily high tides and two low tides experienced along most coasts.

During perigee, when the moon is closest to Earth, those tides become even more extreme, leading to what experts call King Tides.

As a result, numerous weather alerts have been issued, including Coastal Flood Advisories, Coastal Flood Warnings, and Rip Current Statements, from the Carolinas through Florida.

Many coastal communities are no strangers to extreme tidal flooding.

In Charleston, South Carolina, tides routinely force the closure of downtown streets, with floodwater deep enough for vehicles to stall.

Additional communities that could experience flooding include Savannah and Brunswick in Georgia, and St. Augustine, Miami, and Key West in Florida, where drainage systems are usually compromised during high tides.

The FOX Forecast Center said that the flood risk also extends beyond the immediate coast. Water can also back up into tidal rivers, bays, and sounds, such as the Cape Fear River, the Cooper River, Pamlico Sound, Savannah River, and St. Johns River.

The FOX Forecast Center said that the greatest flood threat will occur early this week, but elevated tides will persist into the latter half of the week, too.

Conditions should start to improve by mid- to late-week as winds begin to ease and shift offshore, allowing water levels to gradually recede.

After this week’s event, there are two more Supermoons remaining this year: the Beaver Moon on Nov. 5 and the Cold Moon on Dec. 4. 

Both lunar events are expected to increase tidal levels, but not as significantly as October’s event.