The most significant storm of the season was Hurricane Floyd , a strong Category 4 hurricane that caused devastating flooding along the East Coast of the United States , especially in North Carolina . Damage from the storm totaled approximately $ 6.5 billion ( 1999 USD ) and there were at least 77 fatalities , making it the deadliest hurricane in the United States since Hurricane Agnes in 1972 . Flooding from Floyd in North Carolina followed Hurricane Dennis , a slow and erratic &ndash; moving storm that dropped heavy rainfall in the eastern portion of the state . Tropical Depression Eleven in October contributed to extreme flooding in Mexico , which left 636 people dead and caused $ 491.3 million in damage , though impact could not be distinguished from the storm itself . Hurricane Irene caused extensive flooding in Cuba and Florida , with lesser effects in the Bahamas and North Carolina . Irene was the second &ndash; costliest storm of the season , with about $ 800 million in damage . Hurricane Lenny was an unusual eastward &ndash; moving storm in the Caribbean Sea and a strong late &ndash; season storm . It caused extensive damage in the Lesser Antilles in the month of November . Collectively , the storms of the 1999 Atlantic hurricane season caused at least 123 fatalities and $ 8.19 billion in losses
extreme flooding in Mexico
October 1999 Mexico floods
1999 Atlantic hurricane season