Centro Conjunto de Advertencia de Tifones
Like most of the tropical cyclones of the season, the sixty-sixth formed on September 11, around where Tropical Depression Fifty-Five had formed earlier in the season. The Joint Typhoon Warning Center began following the disturbance, which was out in the open Pacific Ocean. The disturbance was upgraded into a tropical depression on September 12. The depression progressed westward, with the Japan Meteorological Agency following suit as a tropical depression. As the depression became to make a curve towards Japan, the Joint Typhoon Warning Center ceased tracking the depression.