View source for Storm history of Hurricane Katrina

{{merge|Hurricane Katrina|date=January 2024}}
{{Infobox Hurricane History
| Name=Hurricane Katrina
| Type=Hurricane
| Year=2004
| Basin=Atl
| Image location=Katrina 2005 track.png
| Image name=Hurricane Katrina track map
| Formed=August 23, 2005
| Dissipated=August 30, 2005
| 1-min winds=150
| Pressure=902
| Areas=[[Bahamas]], [[South Florida]], [[Cuba]], [[Louisiana]] (especially [[Greater New Orleans]]), [[Mississippi]], [[Alabama]], [[Florida Panhandle]], most of eastern North America
| Hurricane season=[[2005 Atlantic hurricane season]]
}}
{{Katrina}}
The '''storm''' '''history of Hurricane Katrina''' started on August 23, 2012. [[Hurricane Katrina]] was a highly destructive [[Saffir-Simpson Hurricane Scale|Category 5]] [[tropical cyclone|hurricane]] which formed as [[Tropical cyclone#Classifications|Tropical Depression]] Twelve near the [[Bahamas]]. The next day, the tropical depression strengthened to a [[Tropical cyclone#Classifications|tropical storm]], and was named ''Katrina''. Katrina continued on to make [[Landfall (meteorology)|landfall]] on the southern part of the [[U.S. state]] of [[Florida]] as a Category 1 hurricane.

While passing across [[Florida]], Katrina weakened to a tropical storm. However, the warm waters of the [[Gulf of Mexico]] allowed it to [[rapid deepening|rapidly intensify]] to the sixth strongest [[Atlantic hurricane]] in recorded history. Afterwards, Katrina made landfall as a Category 3 hurricane near [[Buras-Triumph, Louisiana|Buras-Triumph]], [[Louisiana]], and once more near the [[Mississippi]]/[[Louisiana]] [[border]]. Katrina did not stop going northward through the central [[United States]] and finally [[Dissipation|dissipated]] near the [[Great Lakes]], where it was absorbed by a [[cold front]].

==Formation==
Tropical Depression Twelve formed over the southeastern [[Bahamas]] at 5:00 p.m. [[EDT]] (2100 [[Coordinated Universal Time|UTC]]) on August 23, 2005. Some of the tropical depression was from the remains of [[Tropical Depression Ten (2005)|Tropical Depression Ten]], which had dissipated from the effects of a nearby upper [[troposphere|tropospheric]] [[trough (meteorology)|trough]]. 

==First landfall==
As the [[atmosphere|atmospheric]] [[Condition|conditions]] surrounding Tropical Depression Twelve were good for [[Tropical cyclogenesis|tropical development]], the system began to strengthen, was upgraded to Tropical Storm status and given the name ''Katrina'' on the morning of August 24. A burst of [[convection]] allowed Katrina to become the fifth hurricane of the 2005 season on August 25, only two hours before it made landfall around 6:30 p.m. [[North American Eastern Time Zone|EST]] (2230 [[UTC]]) between [[Hallandale Beach, Florida|Hallandale Beach]] and [[Aventura, Florida|Aventura]], [[Florida]].

[[File:Katrina 2005-08-25 1630Z.jpg|thumb|right|200px|Hurricane Katrina prior to Florida landfall.]]

Katrina struck the peninsula at a high speed with 80&nbsp;[[miles per hour|mph]] (130&nbsp;[[kilometres per hour|km/h]]) winds, and had a well-defined [[eye (cyclone)|eye]] on [[Weather radar|Doppler weather radar]], which stayed undisturbed throughout its passage over Florida. The storm weakened over land on August 26 to a tropical storm, but regained its strength as a hurricane at 2:00 a.m. EDT (0600 UTC), about one hour after making landfall in Florida. Parts of the [[Florida Keys]] experienced tropical storm force winds throughout August 26, with the [[Dry Tortugas]] briefly experiencing hurricane-force winds.<ref name="KatrinaTCR">Knabb, Richard D.; Rhome, Jamie R. "[http://www.nhc.noaa.gov/pdf/TCR-AL122005_Katrina.pdf Tropical Cyclone Report: Hurricane Katrina]." ''[[National Hurricane Center]].'' December 20, 2005.</ref>

==Gulf of Mexico==
Katrina continued a westerly and west-southwesterly track, which forecast Katrina to move westward into [[New Orleans]].<ref name="NHC disc 014">{{cite web | author= Stewart, Stacy | publisher = [[National Hurricane Center]] | title = Hurricane Katrina Discussion No. 14, 5:00 p.m. EDT |date= August 26, 2005 | accessdate = 2006-09-16 |url= http://www.nhc.noaa.gov/archive/2005/dis/al122005.discus.014.shtml?}}</ref>

[[Image:Katrina vs sea surface height.jpg|thumb|250px|left|Hurricane Katrina encountering the Gulf Loop Current.]]

Right after the storm entered the Gulf of Mexico, the low [[wind shear]], good upper-level outflow, and the warm [[sea surface temperatures]] of the [[Loop Current|Gulf Loop Current]] caused Katrina to [[rapid deepening|intensify rapidly]]. On August 27, the storm was upgraded to Category 3 strength,<ref name="NHC pa 016">{{cite web |author= Knabb, Richard |publisher= [[National Hurricane Center]] |title= Hurricane Katrina Advisory No. 16, 5:00 a.m. EDT |date= August 27, 2005 |accessdate= 2006-09-16 |url = http://www.nhc.noaa.gov/archive/2005/pub/al122005.public.016.shtml?}}</ref> becoming the third major hurricane of the season. An [[eye (cyclone)|eyewall]] replacement cycle inhibited strengthening of its maximum winds for about 18 hours, but nearly doubled the size of the storm as a result.<ref name="KatrinaTCR"/> The storm then began a second period of rapid intensification starting at 7:00 p.m. CDT on August 27, and by 12:40 a.m. CDT on August 28, Katrina was upgraded to a Category 4 hurricane with maximum sustained winds of 145&nbsp;mph (233&nbsp;km/h).<ref name="NHC pa 020">{{cite web |author= Knabb, Richard |publisher= NHC |title= Hurricane Katrina Advisory No. 20, 1:00 a.m. CDT |date= August 28, 2005 |accessdate= 2006-09-16 |url = http://www.nhc.noaa.gov/archive/2005/pub/al122005.public.020.shtml?}}</ref> It became a Category 5 storm by 7:00 a.m. CDT,<ref name="NHC pa 022">{{cite web |author= Knabb, Richard |author2= Richard Pasch |publisher= NHC |title= Hurricane Katrina Special Advisory No. 20, 7:00 a.m. CDT |date= August 28, 2005 |accessdate= 2006-09-16| url = http://www.nhc.noaa.gov/archive/2005/pub/al122005.public.022.shtml?}}</ref> twelve hours after the beginning of the second round of rapid [[intensification]], and reached its peak intensity at 1:00 p.m. CDT with maximum sustained winds of 175&nbsp;mph (280&nbsp;km/h), gusts of 215&nbsp;mph (344&nbsp;km/h) and a central pressure of 902&nbsp;[[mbar]] (26.64&nbsp;[[inHg]]).<ref name="NHC pa 023a">{{cite web |author= Pasch, Richard |publisher= NHC |title= Hurricane Katrina Intermediate Advisory No. 23a, 1:00 p.m. CDT |date= August 28, 2005 |accessdate= 2006-09-16 |url= http://www.nhc.noaa.gov/archive/2005/pub/al122005.public_a.023.shtml?}}</ref> The minimum pressure made Katrina, at the time, the fourth most intense [[Atlantic hurricane]] on record.<ref name="KatrinaTCR"/> As the hurricane came closer to New Orleans, the Weather Forecast Office in [[Slidell, Louisiana]] gave out [[National Weather Service bulletin for New Orleans region|two strongly-worded warnings]] of the storm's danger.

By the afternoon of August 28, the storm was large enough that some areas of the [[Gulf Coast]] were already experiencing tropical storm-force winds. The center of Katrina was about 180&nbsp;[[statute mile]]s (290&nbsp;km) from the mouth of the [[Mississippi River]], but tropical storm-force winds extended 230&nbsp;mi (370&nbsp;km) from the center of the storm, and hurricane-force winds extended about 105&nbsp;miles (170&nbsp;km) away.<ref name="NHC pa 024">{{cite web |author= Pasch, Richard |publisher= NHC |title= Hurricane Katrina Advisory No. 24, 4:00 p.m. CDT |date= August 28, 2005 | accessdate= 2006-09-16|url= http://www.nhc.noaa.gov/archive/2005/pub/al122005.public.024.shtml?}}</ref>

Overnight on August 29, and into the morning of the next day, Katrina quickly weakened (in terms of maximum sustained winds) as it began to enter another eyewall replacement cycle. The inner eyewall disappeared before an outer eyewall had fully formed, which was one of the reasons of its rapid weakening. In 18&nbsp;hours, the hurricane's maximum sustained winds decreased from 170&nbsp;mph (280&nbsp;km/h) to 125&nbsp;mph (205&nbsp;km/h).<ref name="KatrinaTCR"/> However, [[storm surge]]s remained high at landfall because large waves greater than 30&nbsp;feet (9.1&nbsp;m) in height were generated beforehand (with a [[buoy]] recording a 55&nbsp;ft/16.7&nbsp;m wave at sea), when Katrina was at Categories 4 and 5 on the [[Saffir-Simpson Hurricane Scale]]. The waves then combined with the [[storm surge]] of the large Category 3 hurricane.<ref name="KatrinaTCR"/>

==Second and third landfalls==
[[Image:Katrina 2005-08-28 1700Z.jpg|thumb|200px|right|Hurricane Katrina on August 28 at 1:00 p.m. [[EDT]].]]

Katrina made its second landfall at 6:10 a.m. CDT on August 29 as a Category 3 hurricane with winds of 125&nbsp;mph (205&nbsp;km/h) near [[Buras-Triumph, Louisiana|Buras-Triumph]], [[Louisiana]]. Because Katrina had just weakened from Category 4 strength, and also because of the shape of the coastline, Category 4-force winds are believed to have existed on land while the eye was over water. Hurricane-force winds were recorded 120&nbsp;miles (190&nbsp;km) from the center. The storm's central pressure was 920&nbsp;mbar (27.17&nbsp;inHg), and its forward speed was 15&nbsp;mph (10&nbsp;km/h). As it made its way up the eastern Louisiana coastline, most communities in [[Plaquemines]], [[St. Bernard Parish]], and [[Slidell, Louisiana|Slidell]] in [[St. Tammany Parish]] were severely damaged by [[storm surge]] and the strong winds of the eyewall, which also went over eastern [[New Orleans]], creating $1 billion worth of damage to the city from intense [[flood]]ing and wind damage.

The storm weakened just before landfall to Category 3 intensity. This follows the trend of previous strong cyclones in the [[Gulf of Mexico]]: all cyclones with [[atmospheric pressure|minimum central pressures]] of 973&nbsp;mbar (28.73&nbsp;inHg) or less have weakened over the 12&nbsp;hours before making [[Landfall (meteorology)|landfall]] in the [[Gulf Coast of the United States]].<ref name="KatrinaTCR"/>

A few hours later, after weakening slightly, Katrina made its third landfall near the Louisiana-Mississippi [[border]] with 120&nbsp;mph (195&nbsp;km/h) sustained winds and 928&nbsp;mbar (27.37&nbsp;inHg) pressure, still at Category 3 intensity. Its minimum pressure at its second landfall was 920&nbsp;mbar (27.17&nbsp;inHg), making Katrina the third strongest hurricane on record to make landfall on the United States, behind [[Hurricane Camille]]'s 909&nbsp;mbar (26.85&nbsp;inHg) reading in 1969, and the [[1935 Labor Day Hurricane]]'s 892&nbsp;mbar (26.35&nbsp;inHg) record.<ref name="KatrinaTCR"/>

[[Image:Hurricane Katrina LA landfall radar.gif|thumb|250px|left|Radar image of Hurricane Katrina making its second and third landfalls.]]

Because the storm was so large, its highly destructive eye-wall winds and the strong northeastern quadrant of the storm pushed record [[storm surge]]s onshore, smashing all of the Mississippi Gulf Coast, including towns in Mississippi such as [[Waveland, Mississippi|Waveland]], [[Bay St. Louis, Mississippi|Bay St. Louis]], [[Pass Christian, Mississippi|Pass Christian]], [[Long Beach, Mississippi|Long Beach]], [[Gulfport, Mississippi|Gulfport]], [[Biloxi, Mississippi|Biloxi]], [[Ocean Springs, Mississippi|Ocean Springs]], [[Gautier, Mississippi|Gautier]] and [[Pascagoula, Mississippi|Pascagoula]], and, in Alabama, [[Bayou La Batre, Alabama|Bayou La Batre]]. The surges at its peak were at 28&nbsp;feet (8.5&nbsp;m) in [[Bay St. Louis, Mississippi]], and at 13&nbsp;feet (4.0&nbsp;m) as far away as [[Mobile, Alabama]], which saw its highest storm surge since 1917.<ref name="KatrinaTCR"/> Storm surge was particularly high due to the [[hydrology]] of the region, the hurricane's extreme size, and the fact that it weakened only shortly before landfall. As Katrina moved inland diagonally over Mississippi, high winds cut a swath of [[damage]] that affected almost the entire state.<ref name="KatrinaTCR"/>

==Dissipation==
[[Image:Hurricane Katrina after landfall MODIS.jpg|thumb|200px|right|Hurricane Katrina after its third landfall, but still at hurricane strength, over southern [[Mississippi]].]]

Katrina stayed at hurricane strength in [[Mississippi]], but it soon weakened. It lost hurricane strength more than 150&nbsp;miles (240&nbsp;km) inland, near [[Meridian, Mississippi|Meridian]], [[Mississippi]]. Katrina was then lowered into a [[tropical depression]] near [[Clarksville, Tennessee|Clarksville]], [[Tennessee]] and broke in half.<ref name="NHC pa 031">{{cite web |author= Avila, Lixion |publisher= NHC |title= Tropical Depression Katrina Advisory No. 31, 10 a.m. CDT |date= August 30, 2005 | accessdate= 2006-09-16 |url= http://www.nhc.noaa.gov/archive/2005/pub/al122005.public.031.shtml?}}</ref> One half of the storm continued to race northward, affecting the [[Central United States]], and it was last noticeable in the eastern [[Great Lakes]] region. On August 31, it was absorbed by a frontal boundary and became a powerful [[extratropical cyclone|extratropical low]], causing 1.97–6.69&nbsp;[[inch]]es (50–170&nbsp;mm) of [[rain]] in 12 hours. It also caused gale-force wind gusts from 31 to 61&nbsp;mph (50 to 98&nbsp;km/h) in southeastern [[Quebec]] and northern [[New Brunswick]]. In the region of [[Saguenay-Lac-Saint-Jean|Saguenay]] and [[Côte-Nord]], rain caused breakdowns and failure in roads. The Côte-Nord region was isolated from the rest of Quebec for at least 1 week. However, the other half of Katrina broke off in the eastern part of the [[Appalachians]], which caused a major [[tornado outbreak]] in the area from central [[Georgia (U.S. state)|Georgia]] to central [[Pennsylvania]]. The tornadoes were strong, killing two people and creating heavy damage.<ref name="KatrinaTCR"/>

At 11:00 p.m. EDT on August 31, the center of the remaining storm that was once Katrina was absorbed by another weather system in southeastern [[Canada]].<ref name="HPC pa 037">{{cite web |url = http://www.hpc.ncep.noaa.gov/discussions/tcpat2.html |title = Public Advisory 37 for the Remnants of Katrina, 11 p.m. EDT |date = August 31, 2005 |publisher = [[Hydrometeorological Prediction Center]] |accessdate = 2006-09-16 |archive-date = 2006-06-14 |archive-url = https://web.archive.org/web/20060614172742/http://www.hpc.ncep.noaa.gov/discussions/tcpat2.html |url-status = dead }}</ref><ref name= "CHC disc 2006-08-31T0800">{{cite web |url= http://www.atl.ec.gc.ca/weather/hurricane/bulletins/20050831114442.Katrina.txt.en |title= Post-Tropical Storm Katrina Information Statement, 08:00 a.m. EDT |publisher= [[Canadian Hurricane Centre]] |date= August 31, 2005 |accessdate= 2006-09-19 |archive-date= 2011-06-11 |archive-url= https://web.archive.org/web/20110611123322/http://www.atl.ec.gc.ca/weather/hurricane/bulletins/20050831114442.Katrina.txt.en |url-status= dead }}</ref>

==Related pages==
* [[Hurricane Katrina]]
* [[Hurricane Katrina tornado outbreak]]
* [[National Weather Service bulletin for New Orleans region]]

==References==
{{reflist}}

==Other website ==
{{sisterlinks|Hurricane Katrina}}
* [[National Hurricane Center]]'s [http://www.nhc.noaa.gov/pdf/TCR-AL122005_Katrina.pdf Tropical Cyclone Report on Hurricane Katrina]
* [[National Hurricane Center]]'s [http://www.nhc.noaa.gov/archive/2005/KATRINA.shtml archive on Hurricane Katrina]
* [[Hydrometeorological Prediction Center]]'s [http://www.hpc.ncep.noaa.gov/tropical2005/KATRINA/KATRINA_archive.shtml archive on Hurricane Katrina]
* [http://www.hpc.ncep.noaa.gov/tropical/rain/katrina2005.html Hurricane Katrina Rainfall Information from HPC] {{Webarchive|url=https://web.archive.org/web/20150424181227/http://www.hpc.ncep.noaa.gov/tropical/rain/katrina2005.html |date=2015-04-24 }}

[[Category:Hurricane Katrina]]
[[Category:Storm histories of tropical cyclones]]