Key Facts
• At around 11:27 p.m. on the 31st, a moderately strong earthquake occurred in Iwate Prefecture.
• The maximum seismic intensity observed was 4 in Morioka City, Iwate Prefecture.
• The epicenter was offshore Iwate Prefecture at a depth of approximately 30 km.
• The earthquake’s magnitude was estimated at 5.7.
• No tsunami warning was issued following the earthquake.
• Seismic intensities ranged from 4 to 1 across multiple municipalities in Iwate, Aomori, Miyagi, Hokkaido, Akita, Yamagata, Fukushima, Niigata, Ibaraki, Saitama, and Yamanashi prefectures.
• Detailed intensity levels: Intensity 4 in Morioka City; Intensity 3 in 18 municipalities including Ninohe City and Hachinohe City; Intensity 2 in over 40 municipalities; Intensity 1 in numerous other areas.
• Information is based on the Japan Meteorological Agency’s latest announcements and will be updated as new data arrives.
Summary
On December 31 at 11:27 p.m., a moderately strong earthquake struck offshore Iwate Prefecture, registering a magnitude of 5.7 and a maximum seismic intensity of 4 in Morioka City. The quake originated about 30 km below the sea surface. Despite its strength, no tsunami threat was detected. The tremor was felt across a wide region, including parts of Aomori, Miyagi, Hokkaido, Akita, Yamagata, Fukushima, Niigata, Ibaraki, Saitama, and Yamanashi prefectures, with intensities ranging from 4 to 1. The Japan Meteorological Agency continues to monitor the situation and will provide updates as necessary. Residents in affected areas are advised to stay alert and follow official guidance.
