 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 . 
