 During the 1860 Atlantic hurricane season , three severe hurricanes struck Louisiana and the Gulf Coast of the United States within a period of seven weeks . The season effectively began on August 8 with the formation of a tropical cyclone in the eastern Gulf of Mexico , and produced seven known tropical storms and hurricanes until the dissipation of the last known system on October 24 . Six of the seven storms were strong enough to be considered hurricanes on the modern @-@ day Saffir – Simpson Hurricane Scale , of which four attained Category 2 status and one attained Category 3 major hurricane strength . The first hurricane was the strongest in both winds and pressure , with peak winds of 125 miles per hour ( 201 km / h ) and a barometric pressure of 950 millibars ( 28 inHg ) . Until contemporary reanalysis discovered four previously unknown tropical cyclones that did not affect land , only three hurricanes were known to have existed ; all three made landfall in Louisiana , causing severe damage . 
