The 1909 Grand Isle hurricane was a large and deadly Category 3 hurricane that caused severe damage and killed more than 400 people throughout Cuba and the northern coast of the Gulf of Mexico. Forming out of a tropical disturbance just south of Hispaniola on September 13, 1909, the initial depression slowly intensified as it moved west-northwest towards Jamaica. Two days later, the system attained tropical storm intensity and turned northwestward towards Cuba. On September 16, it attained the equivalent of a modern-day Category 1 hurricane on the Saffir–Simpson hurricane scale and further strengthened to attain winds of 100 mph (160 km/h) before making landfall in Pinar del Río Province, Cuba on September 18. After a briefly weakening over land, the system regained strength over the Gulf