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Guide

Tsunami: what to do on the South Carolina coast

Checked October 8, 2026 against the National Tsunami Warning Center, the National Weather Service, the National Hurricane Center, NOAA’s National Centers for Environmental Information, the U.S. Geological Survey, the South Carolina Emergency Management Division, and the county pages linked below.

The Tsunami tile repeats what the National Tsunami Warning Center has said. A damaging tsunami on this coast has never been recorded, and this page says plainly what is and is not known about one, what each alert level means, how to get your county’s alerts, and why the water that usually does the harm here comes from a hurricane instead.

If the ocean does something strange, go to high ground or inland now. The National Weather Service’s natural warnings: a strong or long earthquake; the sea rising like “a fast-rising flood or a wall of water”, or draining away to show the bottom; or a loud roar from the water. Any of those means a tsunami “could arrive within minutes.” Do not wait for an official warning, a phone alert or this website.

Who warns this coast

The National Tsunami Warning Center in Palmer, Alaska, issues tsunami messages for this coast. NOAA gives its area as “coastlines along the continental United States, Alaska, and Canada”, and that includes the Atlantic. Its first messages are built from the earthquake’s location, depth and magnitude, often before any wave has been measured, and they are updated, upgraded or cancelled as more information comes in. On the board, a message naming Beaufort or Colleton County, or the coastal waters from Edisto Beach to Savannah, reaches the Lowcountry board; one naming Charleston County, Charleston Harbor or the waters from the South Santee River to Edisto Beach reaches the Charleston board; one naming Georgetown or Horry County, or the waters from Little River Inlet to the South Santee River, reaches the Grand Strand board.

What is actually known about this coast

The U.S. Geological Survey’s summary is short: tsunamis on the Atlantic and Gulf coasts “are rare, but the risks associated with these natural hazards are high.” The source its project studies most is not a fault off this coast but an underwater landslide on the continental slope, and earthquakes far away, on the Caribbean plate boundary or across the ocean, which can send a wave the whole width of the Atlantic.

NOAA’s historical tsunami database, searched for South Carolina, holds three entries. The 1886 Charleston earthquake is listed on the Cooper River with no wave height recorded. The 1929 Grand Banks earthquake and landslide off Newfoundland is listed at Charleston with a wave of 0.12 metres, about five inches, arriving nearly six hours after the quake. The third, in June 2013, was read on a deep-ocean buoy 370 nautical miles east of Charleston, not on the coast. None did harm here. The record is a reason to know the sea’s own signs above, not a warning to wait for.

What the alert levels mean

In the warning centre’s own definitions and recommended actions:

Getting an official alert

Wireless Emergency Alerts come to a capable phone with nothing to sign up for — the weather service’s words are “No signup is required!” — and it sends them for tsunami warnings, hurricanes and storm surge. They are short. The longer messages come from systems you register for. The state’s emergency management division runs one for the whole state: its CodeRED page reads “Get emergency notifications from SCEMD by phone, text and email.”

The county pages (read October 8, 2026, each from the county’s own site):

Beaufort County’s emergency management page did not answer when this was checked. If you are not sure which system covers your address, ask your county’s emergency management office.

The water that usually does the harm here

On this coast the dangerous rise in the sea is almost always storm surge from a tropical storm or hurricane, and the Lowcountry’s wide marsh and eight-foot tide make the timing matter: a surge on a high tide stands that much higher. The National Hurricane Center calls storm surge “currently the leading cause of fatalities from hurricanes”. That is the Weather tile’s job and the weather service’s storm surge and hurricane warnings’, not this tile’s. Evacuations here are ordered by zone: the state’s Know Your Zone map finds yours from an address, and in the division’s words, “state and local authorities will announce evacuations by these predesignated zones.”

Sources