 While at peak intensity , Rammasun turned northward , steered around the subtropical ridge to its east , and early on July 3 it struck the Japanese island of Miyako @-@ jima . A stationary trough over China weakened the convection on the western periphery of the typhoon , and the eye gradually became less organized . On July 4 , Rammasun began weakening , and by 0000 UTC on July 5 it was located about 280 km ( 175 mi ) east @-@ northeast of Shanghai as a minimal typhoon . Shortly thereafter , Rammasun weakened to tropical stom status . An approaching trough caused the storm to accelerate to the northeast , which weakened the convection and left the circulation exposed . Around 2200 UTC on July 5 , Rammasun made landfall in South Korea , near Seosan or about 70 km ( 45 mi ) northwest of the country ’ s capital of Seoul . The JTWC estimated that the landfall intensity was around 65 km / h ( 40 mph ) . The storm quickly crossed the country , and although the JTWC considered Rammasun dissipated early on July 6 over the country , the JMA continued tracking the storm toward the northeast , declaring the storm extratropical at 1200 UTC that day . Early on July 8 , the JMA reported that the remnants of Rammasun dissipated to the south of Vladivostok . 
