 It tracked to the northwest, and quickly intensified into a typhoon a few hours after developing while located about 250 miles (400 km) south of the Ogasawara Islands.After changing its motion to the west, the typhoon turned sharply northward on July 31, followed by a turn to the east-northeast.The storm passed through the Ogasawara Islands on August 2, and halted its forward motion before turning to the northwest.