Coastal Flood Advisory As Abnormal Tides Hit 11 East Coast States

Eleven states along the U.S. East Coast may face coastal flooding over the next few days due to higher-than-normal tides.

Select counties in Connecticut, New York, New Jersey, Delaware, Maryland, Virginia, North Carolina, South Carolina, Georgia, Florida, and Alabama have been issued Coastal Flood Advisories as a result of possible flooding resulting from the full supermoon high tide on Friday.

Additionally, some areas of the Virginia and South Carolina coast are under a Coastal Flood Warning, and a Coastal Flood Statement has been issued for tiny sections of Virginia, Massachusetts, Maine, and New York.

According to the NWS, a Coastal Flood Advisory is issued when “minor or nuisance coastal flooding is occurring or imminent,” while a Coastal Flood Warning is given when “moderate to major coastal flooding is occurring or imminent,” which may “pose a serious risk to life and property.”

The NWS forecasts that areas under the Coastal Flood Watches and Advisories may see between half a foot and 2 feet of coastal flooding, depending on the properties of the coastline. These warnings and advisories are mostly in place through Thursday and Friday afternoon, and many of the advisories may turn into warnings late Thursday.

“For the Coastal Flood Warning, one to two feet of inundation above ground level expected in low-lying areas near shorelines and tidal waterways,” the National Weather Service Wakefield VA said in a Coastal Hazard Message. “For the Coastal Flood Advisory, up to one foot of inundation.”

“Widespread flooding of vulnerable areas will result in an elevated threat of property damage to homes and businesses near the waterfront and shoreline. Water will be 1 to 2 feet above ground level in some areas resulting in a sufficient depth to close numerous roads and threaten homes and businesses,” the NWS said.

New York may also see up to 2 feet of flooding, with “minor flooding in the more vulnerable locations near the waterfront and shoreline.”

“Some roads and low lying properties including parking lots, parks, lawns, and homes and businesses with basements near the waterfront will experience minor flooding,” the NWS said.

Flooding will be worst in the hours surrounding the high tide, which will vary slightly along the East Coast.

“Take the necessary actions to protect flood-prone property. If travel is required, do not drive around barricades or through water of unknown depth,” the NWS advises.

This flooding is due to the full supermoon on November 15, compounded by coastal storms along the coast.

Tides are influenced by the gravitational pull of both the moon and the sun, so when there is a full moon or a new moon, the Earth, moon, and sun align in a straight line, resulting in a stronger gravitational pull. This alignment creates higher-than-average high tides and lower-than-average low tides, known as spring tides.

A supermoon amplifies the effect of tidal forces, resulting in “king tides”—the highest of high tides. If these high tides align with storms, winds, or low-pressure systems, the coastal flooding potential is especially high.

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