what happens immediately after a hurricane makes landfall
Landfall A tropical cyclone is classified as making landfall when the center of the storm moves across the coast; in strong tropical cyclones this is when the eye moves over land.[1] This is where most of the damage occurs within a mature tropical cyclone, such as a typhoon or hurricane, as most of the damaging aspects of these systems are concentrated near the eyewall. Such effects include the peaking of the storm surge, the core of strong winds coming ashore, and heavy flooding rains. These coupled with high surf can cause major beach erosion. In low-lying areas, the storm surge can stay inland for a long time and mix with chemicals already in the area to create a toxic mess.[citation needed] When a tropical cyclone makes landfall, the eye closes in upon itself due to the weakening process, which causes surf to decrease. Maximum sustained winds will naturally decrease as the cyclone moves inland due to frictional differences between water and land with the free atmosphere.[2]
Preparations for Hurricane Katrina By August 26, the possibility of unprecedented cataclysm was already being considered. Some computer models were putting the city of New Orleans right in the center of their track probabilities, and the chances of a direct hit were forecast at 17% (with strike probability rising to 29% by August 28).[7] This scenario was considered a potential catastrophe because 80% of the New Orleans metropolitan area is below sea level along Lake Pontchartrain. Since the storm surge produced by the hurricane's right-front quadrant (containing the strongest winds) was more than 20Â ft (6 m) near Biloxi, emergency management officials in New Orleans feared that the storm surge could go over the tops of levees protecting the city, causing major flooding.[8] This risk of devastation had been known for some time; previous studies by FEMA and the Army Corps of Engineers had warned that a direct hurricane strike on New Orleans could lead to massive flooding, which would lead to thousands of drowning deaths, as well as many more suffering from disease and dehydration, as the flood waters slowly receded from the city.[9][10][11]