August 18, 1927 Tsunami: Kashima, Japan
A tsunami caused by a magnitude 6.4 earthquake began at Kashima, Japan on August 18, 1927 at 19:28 UTC. The water rose as high as 0.4 meters. Its effects were recorded at 2 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
- August 18, 1927, 19:28 UTC
- Source
- Kashima, Japan
- Cause
- Earthquake
- Earthquake
- Magnitude 6.4, 20 km deep
- Maximum water height
- 0.4 m (1.3 ft)
- Runups recorded
- 2
- Tsunami magnitude (Iida)
- -1.3
- Waters
- Ocean
- How certain
- Definite tsunami
- Source location
- 34.200° N, 142.000° 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:
August 19, 4:28 [local time], 1927, there was a moderate earthquake with source at sea off the Boso Peninsula. It was accompanied by aftershocks and a weak tsunami, which was registered by the tide gauges at Choshi and Mera. Still another weak tsunami of unclear origin was registered approximately 80 minutes later. It was difficult to associate it with any aftershocks, and for this reason Wadati and Iida surmised that it was formed as the result of some reflection of the first 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.
| Where | Country | Km from source | Water height, m | Inland, m | Measured by | First wave, UTC | Deaths |
|---|---|---|---|---|---|---|---|
| Choshi | Japan | 201 | 0.18 | Tide gauge (half the maximum wave height) | day 18, 01:02 | ||
| Mera | Japan | 215 | 0.15 | Tide gauge (half the maximum wave height) |
More
Every tsunami in 1927The 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 1579.