Historic Tsunami

1946 Japan Tsunami

20 December 1946 · Honshu: S Coast · Japan

On 20 December 1946 at 19:19 UTC, a tsunami formed near Honshu: S Coast, Japan. It was caused by a magnitude 8.3 earthquake. Waves reached up to 6.6 m high. It was observed at 304 locations in 3 countries or territories, up to 15,036 km from its source. It killed at least 1,362 people. It is the 42nd deadliest of the tsunamis recorded since 1900.

Date

20 December 1946

Time

19:19 UTC

Cause

Earthquake

Earthquake Magnitude

8.3

Highest Wave

6.6 m

Observation Sites

304

Furthest Reach

15,036 km

Deaths

1,362

Homes Destroyed

11,661

Source Country

Japan

Triggering Earthquake

1946 Nankai Earthquake

Countries and Territories Reached

Number of observations, highest wave and deaths in each country.

• 297Japan · 6.6 m288 deaths
• 6United States of America · 0.2 m
• 1Peru · 0.1 m

Highest Waves

• 6.5 mShirahama · Japan · 81 km
• 6.0 mKamiko · Japan · 82 km
• 5.8 mInamikawaseigan · Japan · 100 km
• 5.5 mKata, Mie · Japan · 98 km
• 5.5 mFukuroko · Japan · 42 km
• 5.5 mGata · Japan · 570 km
• 5.3 mMatsubara · Japan · 110 km
• 5.0 mTosa Bay · Japan · 210 km
• 5.0 mNone · Japan · 158 km
• 5.0 mSakihama · Japan · 160 km

Other Major Tsunamis in the Region

• 1995Kobe, Japan · 0.3 m6,434 deaths
• 1945Tokaido, Japan · 1.0 m2,306 deaths
• 1944Off Southeast Coast Kii Peninsula, Japan · 10.0 m1,223 deaths
• 1927Sw. Honshu Island, Japan · 11.3 m3,022 deaths
• 1923Sagami Bay, Japan · 13.0 m105,385 deaths
• 1909Anegawa, Japan · 1.8 m41 deaths

Sources: NOAA National Centers for Environmental Information, Global Historical Tsunami Database (doi:10.7289/V5PN93H7) · Natural Earth