Accompanying Hurricane Katrina's catastrophic coastal impacts was a moderate tornado outbreak spawned by the cyclone's outer bands. The event spanned August 26–31, 2005, with 57 tornadoes touching down across 8 states. One person died and numerous communities suffered damage of varying degrees from central

Mississippi Mississippi ( ) is a U.S. state, state in the Southeastern United States, Southeastern and Deep South regions of the United States. It borders Tennessee to the north, Alabama to the east, the Gulf of Mexico to the south, Louisiana to the s ...

Pennsylvania Pennsylvania, officially the Commonwealth of Pennsylvania, is a U.S. state, state spanning the Mid-Atlantic (United States), Mid-Atlantic, Northeastern United States, Northeastern, Appalachian, and Great Lakes region, Great Lakes regions o ...

, with

Georgia Georgia most commonly refers to: * Georgia (country), a country in the South Caucasus * Georgia (U.S. state), a state in the southeastern United States Georgia may also refer to: People and fictional characters * Georgia (name), a list of pe ...

sustaining record monetary damage for the month of August. Due to extreme devastation in coastal areas of

Louisiana Louisiana ( ; ; ) is a state in the Deep South and South Central regions of the United States. It borders Texas to the west, Arkansas to the north, and Mississippi to the east. Of the 50 U.S. states, it ranks 31st in area and 25 ...

and Mississippi, multiple tornadoes may have been overlooked—overshadowed by the effects of storm surge and large-scale wind—and thus the full extent of the hurricane's tornado outbreak is uncertain. Furthermore, an indeterminate number of waterspouts likely formed throughout the life cycle of Hurricane Katrina. The outbreak began with an isolated F2 over the

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on August 26; no tornadoes were recorded the following day as the storm traversed the Gulf of Mexico. Four weak tornadoes were observed on August 28 as the hurricane approached land, each causing little damage. Coincident with Katrina's landfall, activity began in earnest on August 29 with numerous tornadoes touching down across Gulf Coast states. Georgia suffered the greatest impact on this day, with multiple F1 and F2 tornadoes causing significant damage; one person died in Carroll County, marking the first known instance of a tornado-related death in the state during August. A record 18 tornadoes touched down across Georgia on August 29, far exceeding the previous daily record of just 2 tornadoes for the month throughout the state. Activity diminished over the subsequent two days as the former hurricane moved northward. Several more tornadoes touched down across the Mid-Atlantic states before the cessation of the outbreak just after midnight local time on August 31.

Background

Hurricane Katrina began as a tropical depression on August 23 near

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. Moving northwest, the intensifying system was named ''Katrina'' the next day; it proceeded to make landfall on the southern tip of

Florida Florida ( ; ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders the Gulf of Mexico to the west, Alabama to the northwest, Georgia (U.S. state), Georgia to the north, the Atlantic ...

as a Category 1 hurricane, causing extensive damage. In crossing Florida, the hurricane weakened to a tropical storm; however, the warm waters of the

Gulf of Mexico The Gulf of Mexico () is an oceanic basin and a marginal sea of the Atlantic Ocean, mostly surrounded by the North American continent. It is bounded on the northeast, north, and northwest by the Gulf Coast of the United States; on the southw ...

allowed it to rapidly intensify to the seventh-strongest Atlantic hurricane on record. Afterward, Katrina made landfall as a Category 3 near Buras-Triumph, Louisiana on August 29, and once more near the Mississippi–Louisiana border. Katrina progressed northward through the

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and finally dissipated on August 31 near the

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, when it was absorbed by a

cold front A cold front is the leading edge of a cooler mass of air at ground level that replaces a warmer mass of air and lies within a pronounced surface Trough (meteorology), trough of Low-pressure area, low pressure. It often forms behind an extratropica ...

. Throughout its path, Katrina was responsible for $125 billion in damage and 1,245–1,836 fatalities. These ranked it as the costliest natural disaster in United States' history and the deadliest since a hurricane in 1928. Small-scale, transient supercells embedded within the outer bands of the hurricane produced numerous tornadoes throughout its path. Unlike supercells over the

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, these storms last no more than a few hours and are often

training Training is teaching, or developing in oneself or others, any skills and knowledge or fitness that relate to specific useful competencies. Training has specific goals of improving one's capability, capacity, productivity and performance. I ...

. Most of the tornadoes occurred in the hurricane's right-front quadrant, where strong low-level wind shear, high moisture content, and low convective available potential energy combined to produce locally favorable tornadic conditions. A study in 2008 conducted through the

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found that the majority of Katrina-related supercells developed inland over the Gulf Coast rather than offshore, a finding contrary to multiple studies of prior tropical cyclones.

Daily statistics

List of tornadoes

Notes

References

External links

*
Storm Storm summary by NWS Jackson, Mississippi

Tornado outbreak summary for Georgia by NWS Peachtree City, Georgia
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Tornado A tornado is a violently rotating column of air that is in contact with the surface of Earth and a cumulonimbus cloud or, in rare cases, the base of a cumulus cloud. It is often referred to as a twister, whirlwind or cyclone, although the ...