Tropical Depression Four-C was a short-lived tropical depression the 2006 Pacific hurricane season. The depression formed from from a persistent low-pressure area south of Oahu on October 13, 2006. The depression did not last long, dissipating from upper-level wind shear on October 14. The remains of the depression caused heavy rainfall and thunderstorms on October 17 in Big Island. The depression proved difficult for the Central Pacific Hurricane Center to forecast. After the depression had dissipated, the system, along with a cold front also affected the island of Maui.