Tsunami Advisory Issued and Lifted After 6.6-Magnitude Earthquake Strikes Southwestern Japan

Japan countryside, Kyushu, Japan
Japan countryside, Kyushu, Japan. Photo by Tayawee Supan on Unsplash

On the evening of January 13, 2025, a significant seismic event rattled southwestern Japan, prompting immediate tsunami advisories and precautionary evacuations. The Japan Meteorological Agency (JMA) reported that a magnitude 6.6 earthquake struck the region at 9:19 p.m. local time, with its epicenter located in the Hyuga-Nada Sea, off the coast of Miyazaki Prefecture, according to AP News.

The quake originated at a depth of approximately 36 kilometers (22 miles) and was initially reported as magnitude 6.9 before being revised to 6.6 by the JMA. The tremors were felt across a wide area in Kyushu, Japan’s southwestern main island.

In response to the earthquake, the JMA issued tsunami advisories for the coastal regions of Miyazaki and Kochi prefectures, warning of potential waves up to one meter (3.2 feet) in height. Residents in these areas were advised to evacuate to higher ground as a precautionary measure. Approximately 30 minutes after the quake, a tsunami measuring 20 centimeters (8 inches) was observed at Miyazaki Port. Fortunately, no significant damage or injuries were reported as a result of the tsunami, and the advisories were lifted before midnight.

“This earthquake was assessed as a reverse fault type earthquake with a pressure axis in the west-northwest and east-southeast direction and was a moment magnitude 6.7 earthquake caused by a part of the boundary between the land plate and the Philippine Sea plate in the expected focal area of ​​the Nankai Trough earthquake,” the Japan Meteorological Agency said, according to People.

Despite the intensity of the earthquake, reports of damage were minimal. A small landslide occurred, blocking a road, and some underground water pipes ruptured in the affected areas. One man in Kyushu sustained minor injuries after falling down stairs during the quake. Train services in Miyazaki were temporarily halted, stranding passengers, but operations resumed shortly thereafter. Importantly, no abnormalities were detected at nuclear power plants in the region, and they continue to operate normally.

Japan’s location along the geologically active “Ring of Fire” makes it particularly susceptible to earthquakes and volcanic activity. The country has implemented advanced safety measures, including strict building codes and comprehensive disaster preparedness programs, to mitigate the impact of such natural disasters. The recent earthquake serves as a reminder of the importance of these measures and the need for continued vigilance.

“An earthquake could occur at any time, and it is important to ensure that preparations for earthquakes are implemented on a daily basis,” officials said in a press conference, according to CNN.

MA has cautioned residents to remain alert for potential aftershocks in the coming days and to stay informed through official channels. While the immediate threat has subsided, authorities emphasize the importance of preparedness and adherence to safety protocols in the event of future seismic activity.

This event also brings attention to the Nankai Trough, a submarine trench off the coast of Japan that has been the site of several historical earthquakes. Experts continue to monitor the area closely, as seismic activity in this region could have significant implications for the Japanese archipelago.