Hurricane Gilbert was a large and extremely powerful tropical cyclone that formed during the 1988 Atlantic hurricane season, which peaked as a Category 5 hurricane. The storm brought widespread destruction to the Caribbean and the Gulf of Mexico, and is tied with 1969's Hurricane Camille as the second-most intense tropical cyclone to make landfall in the Atlantic Ocean. It was also the second most intense tropical cyclone on record in the Atlantic basin in terms of barometric pressure, only behind Hurricane Wilma in 2005. Gilbert was also one of the largest tropical cyclones ever observed in the Atlantic basin. At one point, its tropical storm-force winds measured 575 mi (925 km) in diameter. In addition, Gilbert was the most intense tropical cyclone in recorded history to strike Mexico.

The seventh named storm, third hurricane and first major hurricane of the 1988 Atlantic hurricane season, Gilbert developed from a tropical wave on September 8 while located 400 mi (640 km) east of Barbados. Following intensification into a tropical storm the next day, Gilbert steadily strengthened as it tracked west-northwestward into the Caribbean Sea. On September 10, Gilbert attained hurricane intensity, and rapidly intensified into a Category 3 hurricane on September 11. After striking Jamaica the following day, rapid intensification occurred once again, and the storm became a Category 5 hurricane on the Saffir-Simpson scale with peak 1-minute sustained winds of 185 mph (298 km/h), late on September 13. Gilbert then weakened slightly, and made landfall on the Yucatán Peninsula later that day while maintaining Category 5 intensity. After landfall, Gilbert weakened rapidly over the Yucatán Peninsula, and emerged into the Gulf of Mexico as a Category 2 storm on September 15. Gradual intensification occurred as Gilbert tracked across the Gulf of Mexico, and the storm made landfall as a Category 3 hurricane in mainland Mexico on September 16. The hurricane gradually weakened after landfall, and eventually dissipated on September 19 over the Midwestern United States.

Gilbert wrought havoc in the Caribbean and the Gulf of Mexico for nearly nine days. In total, it killed 318 people and caused about $2.98 billion (1988 USD) in damages along its path. As a result of the extensive damage caused by Gilbert, the World Meteorological Organization retired the name in the spring of 1989; it was replaced with Gordon for the 1994 hurricane season.

The origins of Hurricane Gilbert trace back to an easterly tropical wave—an elongated low-pressure area moving from east to west—that crossed the northwestern coast of Africa on September 3, 1988. Over the subsequent days, the wave traversed the tropical Atlantic and developed a broad wind circulation extending just north of the equator. The system remained disorganized until September 8, when satellite images showed a defined circulation center approaching the Windward Islands. The following day, the National Hurricane Center (NHC) classified it as the twelfth tropical depression of the annual hurricane season using the Dvorak technique, when it was located about 400 mi (640 km) east of Barbados. The depression proceeded toward the west-northwest, and while moving through the Lesser Antilles near Martinique, it gained enough strength to be designated as Tropical Storm Gilbert.

After becoming a tropical storm, Gilbert underwent a period of significant strengthening. Passing to the south of Dominican Republic and Haiti, it became a hurricane late on September 10 and further strengthened to Category 3 intensity on the Saffir–Simpson scale the next day. At that time, Gilbert was classified as a major hurricane with sustained winds of 130 mph (210 km/h) and a minimum barometric pressure of 960 mbar (960 hPa; 28 inHg). On September 12, the hurricane made landfall on the eastern coast of Jamaica at this intensity; its 15 mi (24 km)-wide eye moved from east to west across the entire length of the island.

Gilbert strengthened rapidly after emerging from the coast of Jamaica. As the hurricane brushed the Cayman Islands, a reporting station on Grand Cayman recorded a wind gust of 156 mph (251 km/h) as the storm passed just to the southeast on September 13. Explosive intensification continued until Gilbert reached a minimum pressure of 888 mbar (888 hPa; 26.2 inHg) with maximum sustained flight-level winds of 185 mph (298 km/h), having intensified by 72 mbar in a space of 24 hours. This pressure was the lowest ever observed in the Western Hemisphere and made Gilbert the most intense Atlantic hurricane on record until it was surpassed by Hurricane Wilma in 2005.

Gilbert then weakened somewhat, but remained a Category 5 hurricane as it made landfall for a second time on the island of Cozumel, and then a third time on Mexico's Yucatán Peninsula on September 14. This made it the first Category 5 hurricane to make landfall in the Atlantic basin since Hurricane David hit Hispaniola in 1979. The minimum pressure at landfall in Cozumel was estimated to be 900 millibars (27 inHg), along with maximum sustained winds of 160 mph (260 km/h). The storm weakened quickly while crossing land before it emerged into the Gulf of Mexico as a Category 2 hurricane. Gilbert re-strengthened rapidly, however, and made landfall for a final time as a Category 3 hurricane near La Pesca, Tamaulipas on September 16, with winds of about 125 mph (201 km/h).

On September 17, Gilbert brushed the inland city of Monterrey, Nuevo León before taking a sharp turn to the north. The storm spawned 29 tornadoes in Texas on September 18, and then moved across Oklahoma. It was absorbed by a low-pressure system over Missouri on September 19, and finally became extratropical over Lake Michigan.