Hurricane Katrina

==Meteorological history==
{{Main|Meteorological history of Hurricane Katrina}}
{{For timeline}}
{{storm path|Katrina 2005 path.png|colors=new}}
Hurricane Katrina originated from the merger of a [[tropical wave]] and the mid-level remnants of [[Tropical Depression Ten (2005)|Tropical Depression Ten]] on August 19, 2005, near the [[Lesser Antilles]]. On August 23, the disturbance organized into Tropical Depression Twelve over the southeastern Bahamas. The storm strengthened into [[Tropical cyclone#Tropical storm|Tropical Storm]] Katrina on the morning of August 24. The tropical storm moved towards Florida and became a hurricane only two hours before making [[landfall (meteorology)|landfall]] between [[Hallandale Beach, Florida|Hallandale Beach]] and [[Aventura, Florida|Aventura]] on the morning of August 25. The storm weakened over land, but it regained hurricane status about one hour after entering the Gulf of Mexico, and it continued strengthening over open waters. On August 27, the storm reached Category 3 intensity on the [[Saffir-Simpson hurricane wind scale]], becoming the third [[Tropical cyclone scales#Atlantic, Eastern and Central Pacific|major hurricane]] of the season. An [[eyewall replacement cycle]] disrupted the intensification but caused the storm to nearly double in size.<ref name="KatrinaTCR">{{cite report|url={{NHC TCR url|id=AL122005_Katrina}}|title=Hurricane Katrina: August 23–30, 2005|author=Knabb, Richard D|author2=Rhome, Jamie R|date=December 20, 2005|publisher=United States National Oceanic and Atmospheric Administration's National Weather Service|author3=Brown, Daniel P|author4=National Hurricane Center|access-date=January 8, 2016|format=PDF|type=Tropical Cyclone Report}}</ref> Thereafter, Katrina [[rapid deepening|rapidly intensified]] over the "unusually warm" waters of the [[Loop Current]], from a Category 3 hurricane to a Category 5 hurricane in just nine hours.<ref>{{cite web|author1=Leben, Robert |author2=Born, George |author3=Scott, Jim |url=http://www.colorado.edu/news/releases/2005/358.html|title=CU-Boulder Researchers Chart Katrina's Growth In Gulf Of Mexico|publisher=[[University of Colorado at Boulder]]|date=September 15, 2005|access-date=May 20, 2011|archive-url=https://web.archive.org/web/20090301014255/http://www.colorado.edu/news/releases/2005/358.html|archive-date=March 1, 2009}}</ref>

After attaining Category 5 hurricane status on the morning of August 28, Katrina reached its peak strength at 1800 [[Coordinated Universal Time|UTC]], with maximum sustained winds of {{convert|175|mph|km/h|-1|abbr=on}} and a minimum central [[atmospheric pressure|pressure]] of {{convert|902|mbar|inHg|abbr=on|lk=on}}. The pressure measurement made Katrina the fifth most intense Atlantic hurricane on record at the time, only to be surpassed by Hurricanes [[Hurricane Rita|Rita]] and [[Hurricane Wilma|Wilma]] later in the season; it was also the strongest hurricane ever recorded in the [[Gulf of Mexico]] at the time, before Rita broke the record.<ref name="KatrinaTCR"/> The hurricane subsequently weakened due to another eyewall replacement cycle, and Katrina made its second landfall at 1110 UTC on August 29, as a high end Category 3 hurricane with sustained winds of {{convert|125|mph|km/h|abbr=on}}, near [[Buras-Triumph, Louisiana]]. At landfall, hurricane-force winds extended outward {{convert|120|mi|km}} from the center and the storm's central pressure was {{convert|920|mbar|inHg|abbr=on}}. After moving over southeastern Louisiana and [[Breton Sound]], it made its third and final landfall near the Louisiana–Mississippi border with {{convert|120|mph|km/h|-1|abbr=on}} sustained winds, still at a mid range Category 3 hurricane intensity.<ref>{{Cite news|url=https://weather.com/storms/hurricane/news/atlantic-hurricane-category-five-history-0|title=Monsters of the Atlantic: The Basin's Category 5 Hurricanes|work=The Weather Channel|access-date=September 11, 2017 |archive-url=https://web.archive.org/web/20170906093016/https://weather.com/storms/hurricane/news/atlantic-hurricane-category-five-history-0|archive-date=September 6, 2017|url-status=live}}</ref> Katrina maintained strength well into Mississippi, finally losing hurricane strength more than {{convert|150|mi|km}} inland near [[Meridian, Mississippi]]. It was downgraded to a tropical depression near [[Clarksville, Tennessee]]; its remnants were absorbed by a [[cold front]] in the eastern [[Great Lakes]] region on August 31. The resulting [[extratropical]] storm moved rapidly to the northeast and affected eastern Canada.<ref name="KatrinaTCR"/>