Typhoon Rusa made landfall on the southwest South Korean coast in the late afternoon of August 31, 2002. Although the storm was only of moderate strength, extreme rainfall was produced over the mountainous region near Mount Chiri Park in excess of 80 cm in a 36 hour period. Destructive flooding occurred east of the north-south oriented T’Aebaek mountains of South Korea, although measured precipitation amounts were somewhat less. A numerical simulation of the event was performed using the UW-NMS model to determine the factors leading to the extreme precipitation. Topographical lifting in the immediate vicinity of the heavy precipitation was a primary forcing mechanism; however channeling effects of upstream topography also appeared to form a natural convergence of flow into the slopes of Chiri. In addition, the Sea of Japan itself, helped channel flow in the primary band of Rusa from the south, further focusing precipitation into the Chiri region. Additional analysis of the event will be presented during the oral presentation.