Earthquakes

[bluesboy]

yes, earthquake early warning is very real, and is moving along in America. Up to a minute warning may be possible. Enough to move to a safer place, stop an elevator, stop a train, etc, etc.

https://earthquake.usgs.gov/research/earlywarning/

Due to the geography, in Hawaii it probably won't be quite as useful as on the mainland, but there is still potential.