Tangentially related to Kumamoto: Abnormally low tides portend imminent disaster. Both tsunami and typhoons tend to suck up a lot of water before suddenly spitting it back out. Below top is a photo taken in Tohoku shortly before the tsunami hit; bottom is one of two beached manatees in Florida - apparently, the water withdrew too quickly for them to follow (they’re not the brightest of animals, but then, this is not a normal situation). Fortunately, both were quickly rescued by rolling each onto a tarp and dragging them them to a channel, from whence off they swam. The rescuers than rapidly got the hell off the beach.
Lesson: If you’re at the beach and see something unusual like exposed tako pots or vast expanses of sand, head for the hills. Full article (and more photos) at the link: http://www.huffingtonpost.com/entry/beached-manatees-rescued-low-tide-hurricane-irma_us_59b5b0b8e4b0354e44129193 - William