Coastal flooding in the context of "2016 Atlantic hurricane season"

A flood is an overflow of water (or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are of significant concern in agriculture, civil engineering and public health. Human changes to the environment often increase the intensity and frequency of flooding. Examples for human changes are land use changes such as deforestation and removal of wetlands, changes in waterway course or flood controls such as with levees. Global environmental issues also influence causes of floods, namely climate change which causes an intensification of the water cycle and sea level rise. For example, climate change makes extreme weather events more frequent and stronger. This leads to more intense floods and increased flood risk.

Natural types of floods include river flooding, groundwater flooding coastal flooding and urban flooding sometimes known as flash flooding. Tidal flooding may include elements of both river and coastal flooding processes in estuary areas. There is also the intentional flooding of land that would otherwise remain dry. This may take place for agricultural, military, or river-management purposes. For example, agricultural flooding may occur in preparing paddy fields for the growing of semi-aquatic rice in many countries.

Urban flooding is the inundation of land or property in cities or other built environment, caused by rainfall or coastal storm surges overwhelming the capacity of drainage systems, such as storm sewers. Urban flooding can occur regardless of whether or not affected communities are located within designated floodplains or near any body of water. It is triggered for example by an overflow of rivers and lakes, flash flooding or snowmelt. During the flood, stormwater or water released from damaged water mains may accumulate on property and in public rights-of-way. It can seep through building walls and floors, or backup into buildings through sewer pipes, cellars, toilets and sinks.

There are several types of urban flooding, each with a different cause. City planners distinguish pluvial flooding (flooding caused by heavy rain), fluvial flooding (caused by a nearby river overflowing its banks), or coastal flooding (often caused by storm surges). Urban flooding is a hazard to both the population and infrastructure. Some well known disaster events include the inundations of Nîmes (France) in 1998 and Vaison-la-Romaine (France) in 1992, the flooding of New Orleans (United States) in 2005, and the flooding in Rockhampton, Bundaberg, Brisbane during the 2010–2011 Queensland floods in Australia, the 2022 eastern Australia floods, and more recently the 2024 Rio Grande do Sul floods in Brazil.

A nor'easter (also northeaster; see below) is a large-scale extratropical cyclone in the western North Atlantic Ocean. The name derives from the direction of the winds that blow from the northeast. Typically, such storms originate as a low-pressure area that forms within 100 miles (160 km) of the shore between North Carolina and Massachusetts. The precipitation pattern is similar to that of other extratropical storms, although nor'easters are usually accompanied by heavy rain or snow, and can cause severe coastal flooding, coastal erosion, hurricane-force winds, or blizzard conditions. They tend to develop most often and most powerfully between the months of November and March, because of the difference in temperature between the cold polar air mass coming down from central Canada and the warm ocean waters off the upper East Coast. The susceptible regions—the upper north Atlantic coast of the United States and the Atlantic Provinces of Canada—are generally impacted by nor'easters a few times each winter.

Tropical Storm Claudette was a 1979 tropical cyclone which was the third-wettest tropical cyclone on record in the contiguous United States. The storm caused significant flooding in eastern Texas and western Louisiana in July 1979. The eighth tropical cyclone and third named storm of the 1979 Atlantic hurricane season, Claudette developed from a tropical wave located east of the Windward Islands on July 16. It gradually strengthened and was upgraded to a tropical storm on July 17 and crossed the northern Leeward Islands later that day. As it neared landfall in Puerto Rico early on July 18, upper-level winds weakened it back to a tropical depression. Claudette remained disorganized and the National Hurricane Center operationally reported that it degenerated back into a tropical wave after crossing Puerto Rico. Late on July 18, the depression struck Dominican Republic, emerged into the Caribbean Sea on the following day. Claudette struck western Cuba on July 21, shortly before reaching the Gulf of Mexico and "regenerating" into a tropical cyclone. By July 23, Claudette regained tropical storm intensity and turned northward toward the Gulf Coast of the United States. The storm made landfall near the Texas-Louisiana border late on July 23 as a moderately strong tropical storm. It weakened slowly and drifted over land, lasting until dissipation in West Virginia on July 29.

In the Lesser Antilles, the storm brought heavy rainfall and gusty winds to several islands. Minor flooding occurred in Guadeloupe and Saint Croix. Rainfall exceeding 10 inches (250 mm) in some areas of Puerto Rico led to widespread agricultural damage, flooded homes and streets, and one fatality; losses were estimated at $750,000 (1979 USD). Despite its passage over Hispaniola and Cuba, impact in both regions is unknown. Claudette brought record-breaking rainfall to eastern Texas. In Alvin, 42 inches (1,100 mm) of rain fell in one day, which at one point was the record 24‑hour precipitation amount for any location in the United States. Significant coastal flooding and up to 15 inches (380 mm) of rainfall was reported in Louisiana. Overall, Claudette was responsible for two deaths and $400 million (1979 USD) in damage.