 The meteorological history of Hurricane Ivan , the longest tracked tropical cyclone of the 2004 Atlantic hurricane season , lasted from late August through late September . The hurricane developed from a tropical wave that moved off the coast of Africa on August 31 . Tracking westward due to a ridge , favorable conditions allowed it to develop into Tropical Depression Nine on September 2 in the deep tropical Atlantic Ocean . The cyclone gradually intensified until September 5 , when it underwent rapid deepening and reached Category 4 status on the Saffir @-@ Simpson Hurricane Scale ; at the time Ivan was the southernmost major North Atlantic hurricane on record . 
