August 8, 1993 Tsunami: Guam, Mariana Islands, US Territories

Name: August 8, 1993 Tsunami: Guam, Mariana Islands, US Territories
Start: 1993-08-08
Location: Guam, Mariana Islands, US Territories

August 8, 1993 · 2.4 m · $250 million · Definite tsunami

A tsunami caused by a magnitude 7.8 earthquake began at Guam, Mariana Islands, US Territories on August 8, 1993 at 08:34:24 UTC. The water rose as high as 2.4 meters. Its effects were recorded at 50 places in at least 5 countries.

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

Tsunami warnings in force

The tsunami

Date: August 8, 1993, 08:34:24 UTC
Source: Guam, Mariana Islands, US Territories
Cause: Earthquake
Earthquake: Magnitude 7.8, 59 km deep
Maximum water height: 2.4 m (7.9 ft)
Runups recorded: 50
Tsunami magnitude (Iida): -1
Waters: Ocean
How certain: Definite tsunami
Source location: 12.982° N, 144.801° E

The toll

Injuries: 48 with the earthquake or eruption that caused it
Damage: Limited (under about $1 million); $250 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.

The major earthquake generated a small tsunami that was recorded at tide gauge stations in Guam and Hawaii.

A personal account by a man fishing at Pago Bay (Guam) reported a tsunami followed the earthquake by a matter of minutes. A rapidly rising tide caught his pickup truck parked on the beach and pulled it out to sea. When he returned to retrieve his truck it was stuck in the sand about 50 feet from shore in waist high water. (Reference #459)

The tsunami was recorded in Agana, but the gage with a 15-minute sampling rate produced a poor recording. The tsunami was most strongly observed on the west coast. In addition to the struck that was washed into Pago Bay, other vehicles were washed into the bay at Ylig. The wave was observed from the north coast at Inapsan beach where

vehicles had to drive through water to leave the area to the south coast at Inarajan where the roads were covered with debris. The highest wave seems to have occurred in the Talofoto River where the water rose 2.13 meters at the bridge and inundated the river for a quarter of a mile. (Reference #1315)

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	Measured by	First wave, UTC
Talofofo River, Guam, GU	US Territories	39	2.4	Eyewitness observation of water height
Ylig Bay, Guam, GU	US Territories	45	1.8	Eyewitness observation of water height
Pago Bay, Guam, GU	US Territories	48		Eyewitness observation of water height
Apra Harbor, Guam, GU	US Territories	53	0.08	Tide gauge (half the maximum wave height)	day 8, 08:38
Agana Harbor, Guam, GU	US Territories	55	0.08	Tide gauge (half the maximum wave height)
Chichijima Island	Japan	1,586	0.34	Tide gauge (half the maximum wave height)
Okinawa	Japan	2,297	0.09	Tide gauge (half the maximum wave height)
Hirara	Japan	2,432	0.13	Tide gauge (half the maximum wave height)
Kushimoto	Japan	2,446	0.24	Tide gauge (half the maximum wave height)
Uragami	Japan	2,450	0.21	Tide gauge (half the maximum wave height)
Aburatsu	Japan	2,474	0.46	Tide gauge (half the maximum wave height)
Mera	Japan	2,481	0.43	Tide gauge (half the maximum wave height)
Omaezaki	Japan	2,486	0.3	Tide gauge (half the maximum wave height)
Murotomisaki	Japan	2,493	0.43	Tide gauge (half the maximum wave height)
Owase	Japan	2,494	0.23	Tide gauge (half the maximum wave height)
Tosa-Shimizu	Japan	2,502	0.38	Tide gauge (half the maximum wave height)
Uchiura	Japan	2,513	0.14	Tide gauge (half the maximum wave height)
Toba	Japan	2,514	0.14	Tide gauge (half the maximum wave height)
Shimizu	Japan	2,522	0.2	Tide gauge (half the maximum wave height)
Yokosuka	Japan	2,524	0.06	Tide gauge (half the maximum wave height)
Hososhima	Japan	2,536	0.15	Tide gauge (half the maximum wave height)
Yokohama	Japan	2,542	0.06	Tide gauge (half the maximum wave height)
Wakayama	Japan	2,546	0.04	Tide gauge (half the maximum wave height)
Chiba	Japan	2,547	0.05	Tide gauge (half the maximum wave height)
Kochi	Japan	2,548	0.19	Tide gauge (half the maximum wave height)
Komatsushima	Japan	2,549	0.1	Tide gauge (half the maximum wave height)
Kwajalein, Marshall Islands, MH	Marshall Islands	2,550	0.07	Tide gauge (half the maximum wave height)
Choshi	Japan	2,553	0.09	Tide gauge (half the maximum wave height)
Tokyo	Japan	2,561	0.05	Tide gauge (half the maximum wave height)
Yokkaichiko	Japan	2,569	0.06	Tide gauge (half the maximum wave height)
Onahama	Japan	2,682	0.14	Tide gauge (half the maximum wave height)
Changkang (Taitung)	Taiwan	2,723	0.14	Tide gauge (half the maximum wave height)
Hualien	Taiwan	2,728	0.15	Tide gauge (half the maximum wave height)
Ayukawa	Japan	2,824	0.22	Tide gauge (half the maximum wave height)
Ofunato	Japan	2,900	0.17	Tide gauge (half the maximum wave height)
Miyako	Japan	2,968	0.13	Tide gauge (half the maximum wave height)
Hachinohe	Japan	3,070	0.12	Tide gauge (half the maximum wave height)
Hakodate	Japan	3,209	0.07	Tide gauge (half the maximum wave height)
Urakawa	Japan	3,240	0.14	Tide gauge (half the maximum wave height)
Kushiro	Japan	3,325	0.13	Tide gauge (half the maximum wave height)
Hanasaki	Japan	3,359	0.19	Tide gauge (half the maximum wave height)
Shemya Island, AK, AK	United States	5,120	0.14	Tide gauge (half the maximum wave height)
Adak, Sweeper Cove, AK, AK	United States	5,519	0.06	Tide gauge (half the maximum wave height)
Port Allen, Kauai, HI, HI	United States	5,960	0.1	Tide gauge (half the maximum wave height)
Nawiliwili, Kauai, HI, HI	United States	5,983	0.04	Tide gauge (half the maximum wave height)
Haleiwa, Oahu, HI, HI	United States	6,113	0.07	Tide gauge (half the maximum wave height)
Lahaina, Maui, HI, HI	United States	6,262	0.08	Tide gauge (half the maximum wave height)
Kahului, Maui, HI, HI	United States	6,284	0.06	Tide gauge (half the maximum wave height)
Honokohau, Hawaii, HI, HI	United States	6,337	0.03	Tide gauge (half the maximum wave height)
Kapoho, Hawaii, HI, HI	United States	6,465	0.04	Tide gauge (half the maximum wave height)

Every tsunami in 1993 The 1900s Tsunamis of US Territories The earthquake This day in weather history Alerts 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 2221.