 By that time, there was uncertainty in its future track due to the possible interactions among Iris, Humberto to the northeast, Tropical Storm Karen to the southeast, and the remnants of Tropical Storm Jerry to the west.In addition, after Tropical Storm Luis formed on August 27, there were four active tropical cyclones in the Atlantic.A few days later, there were three simultaneous hurricanes, which is a rare event, when Luis attained hurricane status.