As the weather synoptics of the northern Pacific Ocean transitioned into a late-fall to early winter-type pattern, convection from the monsoon trough extended to the east of the International Date Line. During late November, a westerly disturbance developed into twin troughs on opposite sides of the equator; the one in the Southern Hemisphere ultimately developed into Tropical Cyclone Pam, while the one in the Northern Hemisphere formed into an area of convection about 2000 km (1240 mi) southwest of Hawaii. The disturbance gradually organized as it drifted north-northeastward, and on November 28 it developed into Tropical Depression Five-C about 465 km (290 mi) west-northwest of Palmyra Atoll. Operationally, the Central Pacific Hurricane Center (CPHC) did not begin issuing warnings on the system until December 2.