 A weak tropical disturbance was first reported by the Air France and Iberia airlines east of the Lesser Antilles early on September 21 . Although it was speculated that the disturbance originated from a tropical wave near Cape Verde , the Weather Bureau considered the system too weak to be detected due to a lack of reports from the islands . At 1800 UTC on September 21 , while it was located 350 mi ( 565 km ) east @-@ southeast of Martinique , the disturbance became sufficiently organized for the Weather Bureau to classify it as Tropical Storm Janet , the tenth named storm of the season . Upon classification , Janet quickly intensified as it moved to the west . On September 22 , Janet attained hurricane strength , and proceeded to rapidly intensify as it moved westward across the Windward Islands . By 1200 UTC that day , Janet already attained Category 3 hurricane strength with maximum sustained winds of 120 mph ( 195 km / h ) , before stalling in intensification . 
