Heavy rains, associated with an upper trough, began as early as September 4 on Martinique
accompanied the torrential downpours from the stormitself. An 18-hr. rainfall of 11.85 in. was recordedon
Martinique on September 8. Flooding on the two islands tremendously damaged houses, bridges, roads, and crops.The St. Lucia banana crop was 30 percent destroyed. Total damage on the island was estimated by the government at $3 million and that on Martinique was placed at $4.5 million.

Source: https://goo.gl/sBUqM1