March 13, 1909 Tsunami: Off Boso Peninsula, Japan
A tsunami caused by a magnitude 7.5 earthquake began at Off Boso Peninsula, Japan on March 13, 1909 at 14:29 UTC. Its effects were recorded at 1 place.
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
- March 13, 1909, 14:29 UTC
- Source
- Off Boso Peninsula, Japan
- Cause
- Earthquake
- Earthquake
- Magnitude 7.5, 80 km deep
- Runups recorded
- 1
- Tsunami magnitude (Iida)
- -1
- Waters
- Ocean
- How certain
- Definite tsunami
- Source location
- 34.500° N, 141.500° E
The toll
- Damage
- Limited (under about $1 million) 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.
March 13, 1909, 23:29 [local time], 34.5 N, 141.5 E, shallow depth, magnitude 7.5 MS. Some damage at Yokohama by earthquake. Choshi tide gauge recorded tsunami. (reference #150)
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 | 150 | Tide gauge (half the maximum wave height) |
More
Every tsunami in 1909The 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 1375.