Tsunamis in 1946

August 4, 1946 Tsunami: Northeastern Coast, Dominican Republic

August 4, 1946 · 5 m · 1,790 deaths · Definite tsunami

A tsunami caused by a magnitude 7.9 earthquake began at Northeastern Coast, Dominican Republic on August 4, 1946 at 17:51:05 UTC. The water rose as high as 5 meters. Its effects were recorded at 8 places in at least 4 countries. It killed 1,790 people.

Where the waves reached

The source (white) and every runup with a place, colored by the water height recorded there. A ring is a runup NCEI marks doubtful.

  • Under 1 m
  • 1 to 3 m
  • 3 to 10 m
  • 10 to 30 m
  • 30 m and more
  • Height not recorded

Tsunami warnings in force

The tsunami

Date
August 4, 1946, 17:51:05 UTC
Source
Northeastern Coast, Dominican Republic
Cause
Earthquake
Maximum water height
5 m (16.4 ft)
Runups recorded
8
Tsunami magnitude (Iida)
2.2
Waters
Ocean
How certain
Definite tsunami
Source location
19.250° N, 69.000° W

The toll

Deaths
1,790
Damage
Severe (about $5 to $25 million)
Houses destroyed
Many (101 to 1,000)

Where the literature gives no number, NCEI records a description on a scale of 1 to 4, printed here in its words. Damage is in millions of US dollars of the year of the event, not adjusted for inflation.

What the record says

NCEI’s account, from the sources it cites.

A magnitude 8.1 earthquake devastated the Dominican Republic, extended into Haiti, and shook many other islands. Lynch and Bodle (reference #251) suggest that the epicentral region was very extended. It originated 64 km offshore, northeast of the village of Julia Molina (now called Nagua) in the Mona Passage. The greatest damage and loss of life occurred at Matanzas (Matancitas) and nearby coastal towns where a 2.5 m tsunami flattened homes and buildings. Approximately 1,790 people were killed by the tsunami.

Every runup

Nearest the source first. Heights are above sea level at the time; a tide gauge reads half the wave’s full height.

WhereCountryKm from sourceWater height, mInland, mMeasured byFirst wave, UTCDeaths
Cabo SamanaDominican Republic17Eyewitness observation of water height
MatanzasDominican Republic882.51,000Eyewitness observation of water height1,790
NaguaDominican Republic885Eyewitness observation of water height
Rio BobaDominican Republic945Eyewitness observation of water height
San Juan, PRUS Territories3140.66Tide gauge (half the maximum wave height)day 4, 18:27
BermudaBermuda (UK Territory)1,515Tide gauge (half the maximum wave height)day 4, 19:58
Daytona Beach, FL, FLUnited States1,642Tide gauge (half the maximum wave height)day 4, 21:50
Atlantic City, NJ, NJUnited States2,289Tide gauge (half the maximum wave height)day 4, 22:40

More

Every tsunami in 1946The 1900sTsunamis of Dominican RepublicThe earthquakeThis day in weather historyAlerts in force

Sources

Tsunami events and runups from NOAA’s National Centers for Environmental Information, Global Historical Hazard Database, cited as NCEI/WDS, doi:10.7289/V5PN93H7. Public domain. Read 2026-09-24. NCEI tsunami event 1765.