Japan Powerful Quake

Japan experienced a night of fear and uncertainty after a powerful 7.5-magnitude earthquake struck off the coast of Aomori on Monday, shaking large parts of the northeast and prompting widespread tsunami warnings, evacuations and concerns over a potential larger disaster. Although the immediate danger has eased, authorities have now issued a rare “Japan earthquake megaquake warning”, urging the public to remain vigilant for the next several days.

The tremor, which hit at 11:15 p.m. local time, caused strong and prolonged shaking across Aomori, Iwate and Hokkaido. The Japan Meteorological Agency (JMA) initially warned that tsunami waves as high as 3 meters could hit coastal areas, leading officials to order more than 90,000 people to evacuate from vulnerable regions. At least 30 people were injured, and one fire was reported amid the chaos.

Tsunami Warnings Lifted After Waves Hit Coastline

Shortly after the quake, tsunami waves ranging from 20 to 70 centimeters were observed at multiple coastal monitoring points. Ports in Aomori and Hokkaido reported rising water levels as residents rushed to higher ground in freezing temperatures.

By early Tuesday morning, the JMA downgraded the tsunami warnings to advisories and later lifted them completely. While the waves were smaller than feared, officials emphasized that the threat of strong aftershocks—and potentially larger seismic events—remains high.

Public broadcaster NHK reported that waves up to 1.5 feet were recorded in northern Japan, adding that emergency crews remained stationed along the coastline throughout the night.

Japan Powerful quake Shaking Felt Across High-Rise Buildings

The quake registered an upper level 6 on Japan’s 1–7 seismic intensity scale—strong enough to make movement impossible without crawling. Residents in high-rise buildings reported intense swaying due to “long-period ground motion,” a phenomenon where tall structures oscillate for extended periods after a large offshore quake.

Videos shared on Japanese media showed ceiling lights shaking, furniture toppling over and residents covering their heads as the tremors continued.

Despite the strong shaking, no major structural damage has been reported so far. Thousands of households initially lost power, but electricity was largely restored by Tuesday morning.

Train Services Disrupted, Nuclear Plants Checked

To ensure safety, East Japan Railway suspended several train routes in the region. Other train services across northern Japan experienced delays as safety inspections were carried out. By morning, most lines had resumed reduced operations.

Japan’s nuclear safety protocols were also activated immediately. Tohoku Electric Power and Hokkaido Electric Power confirmed that no irregularities were detected at nuclear facilities, including those near the epicenter.

The International Atomic Energy Agency (IAEA) later confirmed that there were no abnormalities at the Fukushima Daiichi nuclear plant, which remains under long-term decommissioning.

Government Issues Rare Megaquake Alert

Following the 7.5-magnitude tremor, the Japanese government issued its highest-level advisory for the possibility of a “megaquake”, citing increased seismic activity along the Japan Trench and Chishima Trench.

This marks the first time since 2022—when the system was established—that the top-tier alert has been activated.

Key points of the megaquake warning:

• Increased likelihood of a magnitude 8 or 9 earthquake

• Alert covers coastal regions from Hokkaido to Chiba

• Next seven days considered critical

• Communities urged to review evacuation plans

• Residents advised to secure heavy furniture and prepare emergency kits

A JMA spokesperson warned that “powerful aftershocks or an even stronger earthquake could occur” in the coming days.

Prime Minister Sanae Takaichi said emergency teams are on high alert:
“We are closely monitoring the situation. Our priority is the safety of our citizens.”

Japan’s Vulnerability in the ‘Ring of Fire’

Japan is one of the most earthquake-prone nations in the world. Situated on the Ring of Fire, it experiences over 1,500 measurable earthquakes annually, including hundreds strong enough to be felt.

The country accounts for nearly 20% of all magnitude 6+ earthquakes worldwide.

Monday’s quake triggered renewed fears of a repeat of the 2011 Tōhoku earthquake, a magnitude-9 monster that produced a devastating tsunami and triggered meltdowns at the Fukushima nuclear plant—one of the worst nuclear disasters in global history.

Updated Government Report Predicts Severe Megaquake Impact

Just months earlier, Japan’s Cabinet Office updated its projections for a worst-case megaquake. The report warns that a powerful rupture along offshore trenches could result in:

• Up to 300,000 deaths

• Damage equivalent to half of Japan’s GDP

• Economic losses of ¥270 trillion

• Devastating tsunamis reaching much further inland than previously estimated

Experts also noted that inflation, new terrain models and updated flood maps contributed to the increased damage estimate.

Fukushima no Abnormalities, but Long-Term Risks Remain

While Fukushima saw no new safety concerns, the site remains one of the most hazardous in the world. Despite Japan beginning the release of treated radioactive water in 2023, more than 1 million tons of highly radioactive debris remain onsite.

The government and TEPCO aim to complete Fukushima’s cleanup by 2051, though many experts believe the process could take a century or more.

No Tsunami Threat to North America

The U.S. National Tsunami Warning Center confirmed that Monday’s earthquake does not pose a threat to Alaska, British Columbia, Washington, Oregon or California. Monitoring systems continue to track offshore wave patterns, but no alerts have been issued.

Conclusion

Japan may have lifted its tsunami warnings, but the issuance of the Japan earthquake megaquake warning underscores the heightened seismic risk facing the region. Communities along the northeastern coast are urged to remain vigilant, prepare emergency supplies and stay informed through official channels.

As Japan continues to rebuild confidence after Monday’s powerful quake, the nation remains on edge—aware that a larger seismic event could strike without warning.