Historical tsunamis · May 16, 1968, 10:39 AM UTC
1968 Off Coast of Honshu Island tsunami
Japan
The tsunami of May 16, 1968, 10:39 AM UTC originated near Off Coast of Honshu Island (Japan).
Key facts
- Date
- May 16, 1968, 10:39 AM UTC
- Cause
- Earthquake
- Magnitude
- M7.5
- Depth
- 33 km
- Maximum documented water height
- 0.58 m
- Observation records
- 10
- Countries affected
- 2
It was triggered by a magnitude 7.5 earthquake at a depth of 33 km.
The highest documented water height was 0.58 m (Hiroo, Japan).
10 observation sites in 2 countries are recorded.
Map of observation sites
10Each dot is a documented observation site; colour and size show the observed water height. The triangle marks the source.
Tsunami arrival times
Documented arrival times from the NOAA/NCEI database, showing the earliest recorded location per country. Coverage is incomplete: a country without an entry was not necessarily spared.
- 0:00 hEarthquake (origin) · May 16, 1968, 10:39 AM UTC
- 0:28 hJapan · Urakawa · 0.55 m
8 places with a documented arrival time
Observations by country
| Country | Observation records | Maximum documented water height | Deaths | Earliest arrival |
|---|---|---|---|---|
| Japan | 8 | 0.58 m Hiroo | — | 0:28 h |
 Canada | 2 | 0.07 m Tofino (Clayoquot),British Columbia | — | — |
Highest documented water heights
10 / 10Individual documented observations for this event. Heights come from different measurement types and sources; not every location has a measured height.
| Location / station | Observed height | Distance from source | Country |
|---|---|---|---|
| Hiroo · Hokkaido | 0.58 m | 101 km | Japan |
| Urakawa · Hokkaido | 0.55 m | 74 km | Japan |
| Miyako · Iwate | 0.52 m | 214 km | Japan |
| Hachinohe · Aomori | 0.48 m | 146 km | Japan |
| Muroran · Hokkaido | 0.28 m | 173 km | Japan |
| Ofunato · Iwate | 0.23 m | 287 km | Japan |
| Enoshima · Miyagi | 0.14 m | 357 km | Japan |
| Tofino (Clayoquot),British Columbia · Bc Classified as doubtful | 0.07 m | 6,768 km | Canada |
| Ayukawa · Miyagi | — | 370 km | Japan |
| Port Alberni, British Columbia · Bc Classified as doubtful | — | 6,832 km | Canada |
More tsunamis
Source: NOAA National Centers for Environmental Information (NCEI), Global Historical Tsunami Database. Confirmed events only. Deaths and damage are database estimates; older records are incomplete. Water heights come from different types of observation.