The Toyama Bay is a calm sea even if in winter, because it is pretected from the northwest winter monsoon and waves generated by the monsoon by the Noto Peninsula. On the other hand wave disasters occur due to swells on the coast of the Toyama Bay for the period from October to March. The swells are generated by winds due to developed low pressure stayed near Hokkaido in west sea area of Hokkaido, and propagate to the Toyama Bay. The swells which cause disasters in the Toyama Bay are called Yorimawari Waves. Yorimawari waves and invade Toyama Bay from the direction of north-northeast and northeast, deflecting to the right when they across the Tsushima Warm Current. Significant wave periods of the Yorimawari Waves are more than 10 seconds and Significant wave heights of them are more than one meter. The records of wave disasters on the coast of the Toyama Bay, the mechanism of generating the Yorimawari Waves, and preventive measures for wave disasters are investigated here, and the results are reported in this paper.
