July 18, 1961 Tsunami: Ryukyu Islands, Japan
A tsunami caused by a magnitude 6.6 earthquake began at Ryukyu Islands, Japan on July 18, 1961 at 14:04:00 UTC. The water rose as high as 0.2 meters. Its effects were recorded at 6 places.
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
The tsunami
- Date
- July 18, 1961, 14:04:00 UTC
- Source
- Ryukyu Islands, Japan
- Cause
- Earthquake
- Earthquake
- Magnitude 6.6, 60 km deep
- Maximum water height
- 0.2 m (0.7 ft)
- Runups recorded
- 6
- Tsunami intensity (Soloviev-Imamura)
- -3
- Tsunami magnitude (Iida)
- -2.3
- Waters
- Ocean
- How certain
- Definite tsunami
- Source location
- 29.600° N, 131.800° E
The toll
The record gives no deaths, injuries or damage for this tsunami.
What the record says
NCEI’s account, from the sources it cites.
Reference #414:
1961, July 18, 23:04 local time. Validity 4. There was an earthquake with source on the north of the Ryukyu Islands. It was accompanied by a weak tsunami, which was registered by tide gauges.
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 |
|---|---|---|---|---|---|---|---|
| Aburatsu | Japan | 223 | 0.03 | Tide gauge (half the maximum wave height) | day 18, 14:40 | ||
| Kikai Shima | Japan | 230 | 0.08 | Tide gauge (half the maximum wave height) | day 18, 14:32 | ||
| Makurazaki | Japan | 234 | 0.02 | Tide gauge (half the maximum wave height) | day 18, 15:06 | ||
| Naze | Japan | 262 | 0.06 | Tide gauge (half the maximum wave height) | day 18, 14:48 | ||
| Hososhima | Japan | 314 | 0.05 | Tide gauge (half the maximum wave height) | day 18, 14:56 | ||
| Tosa-Shimizu | Japan | 369 | 0.11 | Tide gauge (half the maximum wave height) | day 18, 14:58 |
More
Every tsunami in 1961The 1900sTsunamis of JapanThe 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 1920.