Initial predictions had wave height of 3m. That's high enough to wash a person away were they to stay on the seaside. I would suggest that JMA information be a primary reference in the early hours after a Japan natural disaster instead of the USGS. They have a better handle on event measurements and worst case predictions than the USGS will.
Thankfully your assessment turned out to be more in line with observation.
Thankfully your assessment turned out to be more in line with observation.