M7.5 Quake Strikes Japan, Triggers Tsunami Warning

December 09, 2025: A powerful magnitude 7.5 earthquake struck off the coast of northern Japan late Monday, unleashing widespread panic, moderate damage, and triggering localized tsunami waves. While initial emergency warnings were later lifted, the seismic event prompted the Japan Meteorological Agency (JMA) to issue a rare ‘megaquake’ alert, cautioning residents about the heightened risk of a major follow-up tremor in the coming days.

The Japan Meteorological Agency confirmed the quake’s magnitude at 7.5, revising an earlier estimate of 7.6. The long-duration tremor was felt across several prefectures, including Hokkaido and Tohoku, forcing residents to rush out into the freezing night as buildings swayed violently and alarms blared across smartphones.

Immediate Impact and Eyewitness Accounts

The force of the seismic activity caused immediate disruption and visible damage across the affected regions. Authorities reported at least 30 injuries across Aomori, Hokkaido, and surrounding areas, primarily caused by falling objects. Infrastructure also suffered, with a car reported to have plunged into a road crevasse and numerous buildings sustaining visible façade damage.

Viral videos circulating online captured the chaotic moments, illustrating the sheer intensity of the shaking. Footage from areas like Hachinohe and Takizawa showed water violently sloshing from fish tanks, and shattered windows, with one shop owner describing water flowing from upper floors “like a waterfall.” Eyewitnesses conveyed the severity of the incident, with one convenience store owner in Hachinohe telling local news, “I’ve never experienced such a big shaking.”

Tsunami Threats and Emergency Response

The earthquake immediately triggered tsunami warnings. Waves up to 70 centimeters were recorded at Kuji Port in Iwate, with smaller waves observed along the coasts of Aomori and Hokkaido. While initial advisories had warned of waves as high as three meters, the threat gradually subsided, and all major tsunami warnings were lifted by early Tuesday morning.

In a swift response, more than 28,000 residents were urged to evacuate to higher ground, with some emergency shelters quickly reaching capacity given the near-freezing temperatures overnight. The disruption extended to transport links: bullet-train services on parts of the vital Tohoku Shinkansen line were suspended for extensive safety checks, and approximately 200 passengers were left stranded at New Chitose Airport in Hokkaido.

Utility services also took a hit, with about 2,700 homes in Aomori losing power, though restoration efforts successfully brought most customers back online by the morning. The government confirmed that nuclear facilities in the region, including the Higashidori and Onagawa plants, reported no significant abnormalities. However, officials did note a minor incident at the Rokkasho reprocessing plant, where approximately 450 liters of water spilled from a spent-fuel cooling system, though it was officially deemed not to pose a safety risk.

Prime Minister Sanae Takaichi activated an emergency task force to coordinate the response, emphasizing the need for continued public vigilance. “Please be prepared to evacuate as soon as you feel a tremor,” the Prime Minister urged.

The Haunting Prospect of a ‘Megaquake’

Perhaps the most serious long-term concern is the “megaquake” alert issued by the JMA. Officials warned of an increased likelihood of a magnitude 8-level seismic event in the coming week, covering the Pacific coast from Hokkaido down to Chiba. This alert is a stark reminder of Japan’s inherent seismic vulnerability and its proximity to the fault lines that triggered the devastating 2011 magnitude 9.0 disaster, which claimed nearly 18,500 lives.

JMA official Satoshi Harada stressed the importance of readiness, urging the public to take all necessary precautions. “You need to prepare, assuming that a disaster like that could happen again,” Harada stated, highlighting that residents in 182 municipalities should closely monitor official updates as the nation enters a period of heightened seismic risk.