On the morning of October 7, 1870, a devastating hurricane struck Cuba, bringing floods to the western end of the island. It then raked the Florida Keys with high winds, causing a large number of deaths.
The storm formed somewhere in the eastern Caribbean Sea, but was not detected until it was south of Hispañola, by which time it was already a tropical storm. The storm moved northwestward, between southern Cuba and Jamaica, as it slowly intensified. As it passed south of the Bay of Pigs, it began to rapidly intensify. By the time it made landfall, its maximum sustained winds were estimated at 115 mph (185 km/hr). It moved northward across the narrowest part of the island, exiting between Havana and Matanzas. In Havana, the winds tore part of the roof off of the meteorological observatory at Belen College. In Matanzas, its heavy rains swamped the area rivers, flooding the city and sweeping homes into the sea. Between 800 to 1000 people were killed in Cuba due to this hurricane.
It then moved slowly northeastward through the Florida Straits, its center staying south of the Florida Keys, but nevertheless brought hurricane-force winds to those islands for days. Hundreds more were killed there as its winds brought a storm surge over the low lying island chain. The storm passed over the northern Bahamas and then out to sea, leaving behind an estimated US$12 million in damage.