7.8-magnitude quake off Philippines triggers tsunami waves along Japan's coast
Synopsis
A 7.8-magnitude earthquake off the southern Philippines set off a chain of tsunami alerts across the Pacific on 8 June — pushing waves up to 20 cm onto Japan's coast and prompting the evacuation of over 195,000 people across 10 prefectures. Both Japan and Indonesia lifted all warnings by evening, but the episode is a sharp reminder of how one undersea tremor can mobilise entire national disaster systems simultaneously.
Key Takeaways
A 7.8-magnitude earthquake struck off the southern Philippines on 8 June , confirmed by PHIVOLCS .
Tsunami waves of up to 20 cm were recorded at Chichijima Island , Kushimoto Town , and Miyazaki Port along Japan's coast.
Over 195,000 people across 10 Japanese prefectures were urged to evacuate at the peak of the alert.
All Japan Meteorological Agency tsunami advisories were lifted by 4:50 pm local time .
Indonesia's BMKG also issued and subsequently lifted a tsunami warning after sea levels normalised along northeastern coastal areas.
No casualties were immediately reported in Japan or Indonesia.
A 7.8-magnitude earthquake that struck off the southern Philippines on Monday, 8 June sent tsunami waves measuring up to 20 cm surging along Japan's Pacific coast and other parts of the country, the Japan Meteorological Agency (JMA) confirmed. Advisories were issued across a wide coastal arc before being lifted by late afternoon.
Tsunami Advisories and Observed Waves
The JMA issued tsunami advisories covering coastal areas stretching from Ibaraki Prefecture on Japan's eastern Pacific seaboard all the way south to the island prefecture of Okinawa. Waves of approximately 20 cm were recorded at Chichijima Island in the Ogasawara Islands south of Tokyo, as well as at Kushimoto Town in Wakayama Prefecture and Miyazaki Port in Miyazaki Prefecture. Multiple locations across the prefectures of Kagoshima, Mie, and Miyazaki recorded waves of around 10 cm, while minor waves were also reported in Okinawa and elsewhere. By 4:50 pm local time, all advisories had been lifted.
Evacuations Ordered Across 10 Prefectures
At the height of the alert, over 195,000 people across 10 prefectures — including Chiba, Kochi, and Okinawa — were urged to evacuate, according to Japan's Fire and Disaster Management Agency. The scale of the precautionary mobilisation underlines how seriously Pacific-rim nations treat even moderate tsunami signals following the catastrophic lessons of past events. No casualties were immediately reported in Japan.
Indonesia Lifts Warning After Coastal Monitoring
Indonesia's Meteorology, Climatology and Geophysics Agency (BMKG) also issued a tsunami warning for the country's northeastern coastal areas following the quake, before lifting it hours later after sea-level readings returned to normal. Minor tsunami waves were detected at several coastal monitoring stations in northern Indonesia before conditions stabilised. The earthquake triggered widespread panic among residents in some coastal areas of northeastern Indonesia, local media reported, though no casualties were confirmed there either.
The Epicentre: Southern Philippines
The Philippine Institute of Volcanology and Seismology (PHIVOLCS) confirmed that the magnitude 7.8 offshore earthquake struck waters in the southern Philippines on Monday morning. The tremor was felt across various cities and villages in the region. This comes amid the broader seismic vulnerability of the Pacific Ring of Fire, a belt of intense tectonic activity that encompasses the Philippines, Indonesia, and Japan — making cross-border tsunami coordination a recurring necessity for all three nations.
What Happens Next
With all advisories now lifted and sea levels normalised, authorities in Japan and Indonesia are conducting post-event assessments. The episode serves as a reminder of the speed with which a distant undersea quake can trigger multi-country emergency responses across the Pacific. Regional disaster agencies are expected to review the coordination timeline as part of standard post-event protocols.
Point of View
000 people urged to move is a headline figure, but how many actually did, and how quickly, is the metric that determines whether lives are saved when waves are larger. Regional agencies should publish compliance data, not just advisory timelines. The fact that waves peaked at a modest 20 cm this time should not breed complacency — the 2011 Tohoku disaster began with similar cross-Pacific alerts that were initially underestimated.
NationPress
24 Jul 2026
Frequently Asked Questions
What caused the tsunami warnings in Japan on 8 June?
A 7.8-magnitude earthquake off the southern Philippines on 8 June triggered tsunami advisories along Japan's Pacific coast. The Japan Meteorological Agency recorded waves of up to 20 cm at several locations before lifting all advisories by 4:50 pm local time.
How large were the tsunami waves that hit Japan?
The largest observed waves reached approximately 20 cm, recorded at Chichijima Island in the Ogasawara Islands, Kushimoto Town in Wakayama Prefecture, and Miyazaki Port in Miyazaki Prefecture. Multiple other locations recorded waves of around 10 cm.
How many people were evacuated in Japan?
Over 195,000 people across 10 prefectures — including Chiba, Kochi, and Okinawa — were urged to evacuate at the height of the alert, according to Japan's Fire and Disaster Management Agency.
Did Indonesia also issue a tsunami warning?
Yes. Indonesia's BMKG issued a tsunami warning for northeastern coastal areas after the Philippines earthquake. It was lifted hours later after coastal monitoring stations confirmed sea levels had returned to normal. Minor waves were detected at several northern Indonesian stations.
Were there any casualties reported?
No casualties were immediately reported in Japan or Indonesia following the earthquake and resulting tsunami waves. The tremor was felt across cities and villages in the Philippines and northeastern Indonesia, but no injuries were confirmed in initial reports.
