Tropical Storm Gustav formed on Monday, August 25th, in the Caribbean, south of the Dominican Republic. Gustav rapidly increased to Category One (on the Saffir-Simpson scale) Hurricane status by early Tuesday morning as it headed northwest toward Haiti. As Gustav passed over the mountainous southern peninsula of Haiti later on Tuesday, it weakened back to tropical storm force and began to turn to the southwest toward Jamaica.

Gustav remained a tropical storm as it passed along the southern coast of Jamaica on Thursday and Friday. Interaction with the island of Jamaica impeded its ability to strengthen back to hurricane status before it emerged over the warm waters west of Jamaica.

On Friday evening, August 29th, Gustav regained Category One Hurricane status as it neared the Cayman Islands. Gustav rapidly intensified overnight to a strong Category Two Hurricane with maximum sustained winds of 110 mph early Saturday morning, August 30th. Gustav reached major hurricane status with winds of 120 mph (Category Three) later in the morning as it approached the Isle of Youth in western Cuba. Gustav peak intensity with sustained winds of 150 mph (Category Four) occurred as it passed over the Isle of Youth and the western tip of Cuba on Saturday on August 30th.

By this point, guidance models were fairly consistent in bringing Gustav toward the central/western Louisiana coast on Monday. Gustav's circulation was slightly disrupted as it passed over the western tip of Cuba and gradually weakened as it progressed across the Gulf of Mexico, despite passing over the warm waters northwest of Cuba. By early Sunday afternoon Gustav had weakened slightly to a Category Three Hurricane with sustained winds of 115 mph and was about 270 miles southeast of the mouth of the Mississippi River.

Due to the threat of significant storm flooding associated with the landfall of a major hurricane along the Louisiana Coast, widespread evacuations took place in south Louisiana from August 29th through the 31st. Preliminary estimates indicate that 1.9 million people evacuated from south Louisiana in advance of Hurricane Gustav, Gustav eventually made landfall near Cocodrie, Louisiana, or about 70 miles southwest of New Orleans, on Labor Day morning, September 1st, as a strong Category Two Hurricane with sustained winds of 110 mph. Gustav continued to move inland across south-central Louisiana as a hurricane, dropping to tropical storm status Monday evening.

Wind damage was significant in areas from the south-central coast of Louisiana through greater Baton Rouge with this hurricane. Power was knocked out for days, some areas longer, across this region, with numerous trees down and other related wind damage. A peak wind speed of about 91 mph was reported at Ryan Field in Baton Rouge, 108 and 117 mph near Houma, Louisiana, and 72 mph at Belle Chasse Naval Air Station. Two fatalities and one injury were the result of high winds toppling a large tree into a house in East Baton Rouge Parish. A 45 year old woman also was fatally injured in Livingston Parish when high winds toppled a large tree onto her mobile home. Rainbands associated with the weakening Gustav continued over the region through Tuesday, September 2nd. Tornadoes were reported near Abita Springs and Bush in St Tammany Parish, and Westwego in Jefferson Parish on Tuesday afternoon and evening. Damage included 35 to 40 structures damaged around Westwego, including 15 total losses.

Storm surge was a significant problem in parts of Mississippi and Louisiana as Gustav moved onshore. At Bay St Louis in Hancock County, Mississippi,water levels were nearly 10 feet above normal on Monday morning. Storm tides of 12.00 feet were measured at Black Bay in Plaquemines Parish, Louisiana, 10.50 feet at the Industrial Canal in Orleans Parish, and 9.50 feet at Bayou Dupre in St Bernard Parish. Major beach erosion was observed near Grand Isle in Jefferson Parish with 4.49 feet and Port Fourchon in Lafourche Parish with 4.48 feet of surge. Additional flooding occurred around Lakes Pontchartrain and Maurepas as southeast and east winds pushed water into the lakes thus parts of St John the Baptist, Ascension, Livingston, Tangipahoa, and St Tammany Parishes. Storm surge in the tidal lakes also caused water to back up into the rivers that drain into the lakes including the Amite, Comite, Tickfaw, Natalbany, Tangipahoa, Tchefuncte, Bogue Falaya, and Atchafalaya Rivers in Louisiana, and the Jourdan, Wolf, Biloxi, Tchoutacabouffa Rivers in coastal Mississippi.

Finally, heavy rainfall affected parts of the area, including greater Baton Rouge and New Orleans. In the period from Sunday the 31st through Wednesday the 3rd, there were reports of 11.22" in Brusly, West Baton Rouge Parish, 8.11" in Mandeville, St Tammany Parish, 8.15" in Livingston, Livingston Parish, and 8.91" in Woodville, Wilkinson County, Mississippi.