Japan on High Alert Following 7.5 Magnitude Earthquake and Tsunami Warnings
Tsunami Threat Following Earthquake
File image of Kushiro Port in Hokkaido, on Japan’s Pacific coast under tsunami wave alert. (Photo: @takabo77/X)
Tokyo, Apr 20: Concerns over tsunami waves reaching heights of up to 3 meters have emerged for Japan’s northeastern coastline following a significant earthquake measuring 7.5 on the Richter scale, which occurred off the Sanriku coast. This prompted immediate evacuation orders across several prefectures.
The Japan Meteorological Agency has issued warnings indicating that tsunami waves could impact the Pacific coasts of Aomori, Iwate, and Hokkaido, with the possibility of larger waves following the initial reports.
Initial observations indicated smaller waves, but the situation remains fluid. Kuji Port in Iwate recorded the largest wave so far at 80 cm.
Reports indicate that a 30-cm tsunami was detected at Hachinohe Port in Aomori, while Erimo in Hokkaido experienced a 20-cm wave. Thousands of coastal residents have been ordered to evacuate.
According to local news sources, Kuji Port recorded an 80-cm tsunami, and Miyako Port also in Iwate saw a 40-cm wave, with expectations of more waves to come. Other areas along the coast are also under alert.
Officials have emphasized that tsunami waves can arrive in multiple surges and may increase in strength over time, maintaining the risk of higher waves.
The earthquake struck at 4:53 PM local time at a shallow depth of 10 km, registering a seismic intensity of upper 5 in parts of Aomori. The epicenter was located at 39.8°N latitude and 143.2°E longitude, with the magnitude initially reported as 7.4 before being updated to 7.5.
Prime Minister Sanae Takaichi has urged residents in the affected areas to seek higher ground due to the potential for larger waves.
No irregularities have been reported at nuclear facilities in Aomori and Miyagi prefectures, and operators of the Fukushima Daiichi and Daini plants have confirmed that everything is normal.
Transport services have faced disruptions, with the Tohoku Shinkansen line between Tokyo and Shin-Aomori temporarily suspended as a precautionary measure.
Japan's Pacific coastline, part of the seismically active Ring of Fire, is always at risk of earthquakes and tsunami threats.
A similar earthquake of 7.5 magnitude in December 2025 had prompted warnings in the same region, which were later lifted.