A tsunami warning has been issued for the Miyagi Prefecture, marked in red on the map above.
The same area was hit by a devastating earthquake and tsunami in March 2011.
That quake triggered fuel-rod meltdowns at the Fukushima nuclear plant, causing radiation leakage, contamination of food and water and mass evacuations in the world's worst nuclear crisis since Chernobyl in 1986.
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Rain spreading eastwards throughout the day.
"His fiancee gave birth this morning, of all mornings! We were scared because we've got Glastonbury tonight", said co-singer Chloe Rhodes.
Festival-goers have been enjoying the second day of the Glastonbury festival.