The present study shows that an asymmetrical meteorological field of pressure and wind reproduced by the mesoscale weather forecast model in a storm surge simulation is able to account for the highest surge elevation with a time-lag of 15 hours after making landfall of Typhoon Songda in 2004. It was found that Coriolis force in the momentum equations is a predominant factor of the highest surge elevation. This study also evaluates the effect of river discharges; however, there is insignificant contribution to the skew storm surge.
In Japan the highest storm surge elevations occur simultaneously with landfall of typhoons along the coasts of the Pacific Ocean, while the highest surges occur 10 ~ 15 hours after landfall for the Sanin Coast of the Japan Sea, especially, at Sakai Minato shown in Figs. 1a and 1b. The highest surge was, for instance, observed at Sakai Minato by Typhoon Songda (9th ~ 15th September 2004) which was located off the deep water near 40ºN. The abnormal surge elevations were measured at Sakai Minato during several typhoon events. While the numerous studies have been carried out for the storm surge in the Pacific Ocean, understanding of the storm surges with a time lag on the Sanin Coast in the Japan Sea is poor relatively. Yamashita et al. (2008) studied the storm event in the central Japan Sea in February 2008 using an atmosphere-ocean coupled model and observed tidal data. However, they did not take the delayed storm surge into consideration in the study. Yasuda et al. (2008, 2009ab) carried out for storm surge simulations in the Seto Inland Sea using meteorological forcing reproduced by the Weather Research and Forecasting model (WRF) developed by Skamarock et al. (2008) with 4 dimensional data assimilation and different nesting schemes.
