when is a hurricane considered to make 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]
Hurricane Andrew Andrew began as a tropical depression over the eastern Atlantic Ocean on August 16. After spending a week without significantly strengthening itself in the central Atlantic, it rapidly intensified into a powerful Category 5 hurricane while moving westward towards the Bahamas on August 23. Though it briefly weakened to Category 4 while traversing the Bahamas, it regained its Category 5 status before making landfall in Florida on Elliott Key and Homestead on August 24. With a barometric pressure of 922 mbar (27.23 inHg) at the time of landfall in Florida, Andrew is the fourth most intense hurricane to strike the United States. Several hours later, the hurricane emerged over the Gulf of Mexico at Category 4 strength, with the Gulf Coast of the United States in its path. After turning northwestward and weakening further, Andrew moved ashore near Morgan City, Louisiana, as a low-end Category 3 storm. After moving inland, the small hurricane curved northeastward and rapidly lost its intensity, merging with a frontal system over the southern Appalachian Mountains on August 28.
Hurricane Harvey Hurricane Harvey was an extremely destructive Atlantic hurricane which became the first major hurricane[nb 1] to make landfall in the United States since Wilma in 2005, ending a record 12-year span in which no hurricanes made landfall at such an intensity in the country. In a four-day period, many areas received more than 40 inches (100 cm) of rain as the system slowly meandered over eastern Texas and adjacent waters, causing catastrophic flooding. With peak accumulations of 64.58 in (164.0 cm), Harvey is the wettest tropical cyclone on record in the United States. The resulting floods inundated hundreds of thousands of homes, displaced more than 30,000 people, and prompted more than 17,000 rescues.
Hurricane Harvey After striking land, the storm moved over the Copano Bay and made a second landfall in Texas just north of Holiday Beach at 06:00 UTC on August 26 as a Category 3 hurricane.[31] Afterwards, rapid weakening ensued as its speed slowed dramatically to a crawl, and Harvey weakened to a tropical storm at 18:00 UTC on August 26.[32] For about two days the storm stalled just inland, dropping very heavy rainfall and causing widespread flash flooding. Harvey's center drifted back towards the southeast, positioning itself near or just off the Texas coast at Matagorda by 15:00 UTC on August 28.[33] Once offshore, convection blossomed and allowed the once-exposed low-level circulation to become obscured. An Air Force reconnaissance plane investigating the system during the afternoon of August 29 found that maximum winds had increased to 50 mph (85 km/h).[34] Around 09:00 UTC the next morning, Harvey made its third and final landfall just west of Cameron, Louisiana, with winds of 45 mph (75 km/h).[35]