The ground shook for seven minutes straight. Buildings swayed in Tokyo. Coastal sirens wailed across northeastern Japan. And for millions of people who remember 2011, the fear was immediate and overwhelming.
What Happened Today: The Full Picture
A three meter tsunami warning was issued for Japan after a strong 7.4 magnitude earthquake struck off the northeastern coast according to the Japan Meteorological Agency and the US Geological Survey. Japan's national agency later revised the magnitude up to 7.7. Fidelity
The Japan Meteorological Agency initially issued a three meter tsunami warning for Iwate prefecture and parts of Hokkaido and Aomori. It also issued an advisory in other areas of northeastern Japan estimating a tsunami of up to one meter. Fidelity
The quake hit on Monday at 4:53pm local time in waters off Iwate prefecture on the Pacific coast. It was felt across a wide area shaking buildings in Tokyo hundreds of kilometres to the south. Kiplinger
Seven minutes of shaking. That is not a tremor. That is a message from the earth.
The Tsunami: What Actually Hit the Coast
The warning was terrifying. The reality was closer to a miracle.
Tsunami waves of up to 2.5 feet were reported. Authorities had warned waves could reach as high as 10 feet but no significant damage or injuries were reported. Fidelity
The quake triggered an 80 centimeter tsunami at Kuji Port in Iwate Prefecture while Miyako Port also in Iwate saw a 40 centimeter tsunami. Waves were also forecast to arrive at other locations across a wide swath of the prefecture coast. In Hokkaido the town of Urakawa observed 40 centimeter tsunami. At Aomori's Hachinohe Port a 30 centimeter tsunami was recorded. Nasdaq
There were no immediate reports of casualties or major damage according to Japan's top government spokesperson Minoru Kihara. TradingHours.com
The worst did not happen today. But the warning that came after the quake is what has everyone truly worried.
The Mega Quake Warning Nobody Is Talking About
This is the part of the story most news outlets are burying. And it is the most important part.
Authorities warned residents of northeastern Japan to prepare for an even larger earthquake after the magnitude 7.7 quake struck. Residents in areas where a special advisory has been issued covering 182 municipalities from Hokkaido to Chiba Prefecture should be on alert and ready to evacuate at any moment. Nasdaq
There was a 1 percent chance for a mega quake compared to the 0.1 percent chance during normal times officials said. Fidelity
That sounds small. But consider this — the probability of a devastating mega earthquake just increased ten times overnight. And it covers 182 municipalities.
The JMA has had a system in place since 2022 where if a magnitude 7 level earthquake strikes off the coast of Iwate and Hokkaido it will consider issuing an alert for a potentially stronger quake called a subsequent quake advisory given similar instances in the past. Nasdaq
This advisory does not happen often. When it does, Japan listens.
Complete Earthquake Facts Right Now
Detail | Information |
|---|---|
Magnitude | 7.7 confirmed by JMA |
Location | Off coast of Iwate Prefecture |
Depth | 20 kilometres |
Tsunami Warning Issued | Yes — up to 3 metres initially |
Current Status | Downgraded to advisory |
Evacuations Ordered | 171,957 people across 5 prefectures |
Highest Wave Recorded | 80 cm at Kuji Port Iwate |
Casualties | None reported so far |
Power Outages | 200 across affected areas |
Mega Quake Risk | 1 percent — 10x higher than normal |
Advisory Valid Until | April 27 |
The Ghost of 2011: Why Every Japanese Person Felt This Differently
The alerts and warnings were a stark reminder of the March 11 2011 Great East Japan Earthquake and tsunami that struck the area leaving nearly 20,000 people dead and forcing some 125,000 people to evacuate. Nasdaq
It has been more than 15 years since Japan was hit by a 9.0 magnitude earthquake and tsunami that left 22,000 people dead and forced nearly half a million to flee their homes. Nasdaq
For the people of Iwate and the surrounding coastal prefectures today was not just an earthquake. It was a memory. A trauma. A test of everything they rebuilt since 2011.
Port towns like Otsuchi and Kamaishi — both devastated in 2011 — issued evacuation orders again today. The same streets. The same sirens. The same fear.
A real life observation: A resident of Iwate who survived 2011 described hearing today's tsunami siren as the sound that changes how your body moves. You do not think. You just run.
"Tsunami waves are expected to hit repeatedly. Do not leave safe ground until the warning is lifted."
Japan's Response: Government Acts Fast
Prime Minister Sanae Takaichi said the government had set up a crisis management team and was working to assess the impact of the earthquake. For those of you who live in areas for which the warnings have been issued please evacuate to higher safer places such as higher ground she told reporters. Kiplinger
Several port towns including Otsuchi and Kamaishi both hard hit by the massive earthquake and tsunami in 2011 earlier issued evacuation orders for thousands of residents. Fidelity
JMA officials emphasized that the region which has experienced repeated earthquakes over short periods in the past should be on alert for more strong quakes over the next week especially the next two to three days. Nasdaq
The next 72 hours are the most dangerous window. Japan knows this. And Japan is ready.
Nuclear Plants: The Question Everyone Is Asking
After 2011 this is always the first fear.
No abnormalities were reported at the Fukushima Daiichi Fukushima Daini and other nuclear power plants their operator said. Fidelity
That is the single most important sentence in this entire story for millions of people. The nuclear plants are safe. For now.
Japan rebuilt its entire nuclear safety infrastructure after 2011. Today was the first real test of that system at scale. It held.
What Happens Next: The Warning That Stays in Place
The current advisory will remain in place until April 27. Residents have been urged to reconfirm their evacuation plans including escape routes and ways of communicating with family. Nasdaq
Unlike ordinary ocean waves tsunamis carry an enormous volume of water and arrive as a sustained flood rather than a dramatic crashing wave which makes them deceptively dangerous. Even a wave just 1 foot high carries enough force to knock people off their feet sweeping along debris such as fallen trees and overturned cars. A retreating wave is equally lethal pulling people off land and dragging them out to sea. Fidelity
"Even waves that do not look dramatic can still be dangerous. A tsunami does not need to be towering to cause harm."
Conclusion: Not Over Yet
Today Japan dodged the worst. No deaths. No major damage. Nuclear plants secure. Tsunami warning downgraded.
But the advisory stays in place until April 27. The mega quake risk is ten times higher than normal. And the next two to three days remain the most critical window.
Japan is one of the most earthquake prone countries in the world. It lies on the Ring of Fire an area of intense seismic and volcanic activity. About 10 percent of the world's earthquakes occur in and around Japan and Japan accounts for roughly 20 percent of the world's magnitude 6 plus earthquakes. Fidelity
Japan has faced this before. Japan has survived this before. And Japan is not standing down until April 27.
"Please take anti-disaster steps while embracing the idea that one must protect one's own life."
