January 24, 1948 Tsunami: Sulu Sea, Philippines
A tsunami caused by a magnitude 7.8 earthquake began at Sulu Sea, Philippines on January 24, 1948 at 17:46:43 UTC. Its effects were recorded at 5 places. It killed 74 people, counting the earthquake or eruption that caused it.
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
Travel times
How long the first wave took to reach each part of the ocean, one line for each hour up to 24, estimated from the source and the depth of the sea.
The travel times are computed in your browser, which needs JavaScript.
- 1 to 4 hours
- 5 to 6 hours
- 7 to 14 hours
- 15 hours and more
Computed in your browser the way NOAA’s own travel time maps are: the wave travels at the square root of gravity times the depth, over NOAA’s ETOPO1 depths averaged to a 10 arc-minute grid. Checked against NOAA NCEI’s maps for 21 tsunamis over the first 24 hours, these lines fall within 10 minutes of NCEI’s at half the points compared and within 52 minutes at 9 in 10. They give when the first wave could arrive, not how high it is; bays, harbors and island chains finer than the grid can see it later. Not for use in a warning: see tsunami.gov.
The tsunami
- Date
- January 24, 1948, 17:46:43 UTC
- Source
- Sulu Sea, Philippines
- Cause
- Earthquake
- Earthquake
- Magnitude 7.8, 15 km deep
- Runups recorded
- 5
- Tsunami intensity (Soloviev-Imamura)
- 1.5
- Tsunami magnitude (Iida)
- 1
- Waters
- Ocean
- How certain
- Probable tsunami
- Source location
- 10.714° N, 122.235° E
The toll
- Deaths
- 2; 74 with the earthquake or eruption that caused it
- Damage
- Limited (under about $1 million); $3.5 million with the earthquake or eruption that caused it
- Houses destroyed
- Many (101 to 1,000) with the earthquake or eruption that caused it
- Houses damaged
- Many (101 to 1,000) with the earthquake or eruption that caused it
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.
Reference #414:
1948, January 25, 1:47 [local time]. There was a destructive earthquake on Panay Island. It was especially strong at Iloilo and Jaro. Twenty people died. Cracks more than 100 m long appeared in the ground. Large lanslides came down from the hillsides, low-lying plantations subsided and the principal water mains burst. The banks where fish were caught were washed out by the sea. Two people drowned in tsunami waves at Iloilo.
Reference #79:
1948, January 24, 17:47 UTC, 10.5N, 122E, shallow depth, magnitude 8.2 MS. Two deaths at Iliolo Strait.
Reference #9750:
The report also mentioned sea waves along Iloilo Strait causing the deaths of two persons [...] Fish corals from the Iloilo shore towns of Oton to San Joaquin were destroyed by tsunami. Damage was estimated to be P 250,000. The fish corals were detached from the log moorings.
Every runup
Nearest the source first. Heights are above sea level at the time; a tide gauge reads half the wave’s full height.
| Where | Country | Km from source | Water height, m | Inland, m | Measured by | First wave, UTC | Deaths |
|---|---|---|---|---|---|---|---|
| Miagao, Iloilo | Philippines | 8 | Eyewitness observation of water height | ||||
| San Joaquin, Iloilo | Philippines | 17 | Eyewitness observation of water height | ||||
| Tigbauan, Iloilo | Philippines | 17 | Eyewitness observation of water height | ||||
| Iloilo | Philippines | 36 | Eyewitness observation of water height | 2 | |||
| Guimaras Island | Philippines | 40 | Eyewitness observation of water height |
More
Every tsunami in 1948The 1900sTsunamis of PhilippinesThe 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 1777.