Looking at https://tsunami.gov/, it seems like they do have a 4 tier system, but they jumped straight to the highest tier in this case?
It's a complication that will never happen, but sometimes I think it would be cool if HN had a way of authenticating experts and giving them flair. So many legit smart people here.
https://www.tsunami.gov/events/PAAQ/2024/12/05/so1aq0/1/WEAK...
(Some of my job requires me to deal with natural disaster public warnings; but not tsunami specifically)
(I'm late to the party. The warning has since been cancelled: https://www.nbcbayarea.com/news/california-earthquakes-tsuna...)