When monster Typhoon Haiyan slammed the Philippines in early November, it inflicted especially severe damage on Leyte Island, where the city of Tacloban was engulfed by a massive storm surge.

Experts said the devastation was caused mainly by two factors — the powerful gusts of the super typhoon and an elongated shallow bay. Since Japan has similarly shaped areas, including Osaka and Tokyo bays, experts warn that what happened in the Philippines could strike at any time in the Japanese archipelago.

Haiyan's storm surge washed away hundreds of buildings, leaving mountains of rubble throughout Tacloban and wiping out other cities and towns in the area.