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Tropical Depression Ten (2005)
Encyclopedia
Tropical Depression Ten was the tenth tropical cyclone
of the record-breaking 2005 Atlantic hurricane season
. It formed on August 13 from a tropical wave
that emerged from the west coast of Africa on August 8. As a result of strong wind shear
, the depression remained weak and did not strengthen beyond tropical depression status. The cyclone degenerated on August 14, although its remnants partially contributed to the formation of Tropical Depression Twelve, which eventually intensified into Hurricane Katrina
. The cyclone had no effect on land, and did not directly result in any fatalities or damage.
emerged from the west coast of Africa and entered the Atlantic Ocean. Tracking towards the west, the depression began to exhibit signs of convective organization
on August 11. The system continued to develop, and it is estimated that Tropical Depression Ten formed at 1200 UTC on August 13. At the time, it was located about 1600 miles (2,574.9 km) east of Barbados
. Upon its designation, the depression consisted of a large area of thunderstorm activity, with curved banding features and expanding outflow
. However, the environmental conditions were predicted to quickly become unfavorable. The depression moved erratically and slowly towards the west, and wind shear
inhabited any significant intensification. Late on August 13, it was "beginning to look like Irene
-junior as it undergoes southwesterly mid-level shear beneath the otherwise favorable upper-level outflow pattern". The wind shear was expected to relent within 48 hours, prompting some forecast models to suggest the depression would eventually attain hurricane status.
By early August 14, the shear had substantially disrupted the storm, leaving the low-level center of circulation
exposed from the area of convection, which was also deteriorating. After meandering, the storm began to move westward. Forecasters expected it to resume a northwestward track as high pressure
to the south of Bermuda
was forecasted to weaken and another high was predicted to form southwest of the Azores
. By 1800 UTC on August 14, the strong shear had further weakened the storm, and it no longer met the criteria for a tropical cyclone. It degenerated into a remnant low, and the National Hurricane Center issued their final advisory on the cyclone. Moving westward, it occasionally produced bursts of convective activity, before dissipating on August 18.
Tropical Depression Twelve formed over the southeastern Bahamas at 2100 UTC on August 23, partially from the remains of Tropical Depression Ten. While the normal standards for numbering tropical depressions in the Atlantic
stipulate that the initial designation be retained when a depression regenerates, satellite imagery indicated that a second tropical wave
had combined with Tropical Depression Ten north of Puerto Rico
to form a new, more complex weather system, which was then designated as Tropical Depression Twelve. In a re-analysis, it was found that the low-level circulation of Tropical Depression Ten had completely detached and dissipated; only the remnant mid-level circulation moved on and merged with the second tropical wave. As a result, the criteria for keeping the same name and identity were not met. Tropical Depression Twelve later became Hurricane Katrina
.
, no tropical cyclone watches and warnings were issued for any land masses. No effects, damages, or fatalities were reported, and no ships reported tropical storm-force winds in association with the depression. The system did not attain tropical storm status; as such, it was not designated a name by the National Hurricane Center
. The storm partially contributed to the formation of Hurricane Katrina, which became a Category 5 hurricane on the Saffir-Simpson Hurricane Scale
and made landfall in Louisiana
, causing catastrophic damage. Katrina was the costliest hurricane, and one of the five deadliest, in the history of the United States.
Tropical cyclone
A tropical cyclone is a storm system characterized by a large low-pressure center and numerous thunderstorms that produce strong winds and heavy rain. Tropical cyclones strengthen when water evaporated from the ocean is released as the saturated air rises, resulting in condensation of water vapor...
of the record-breaking 2005 Atlantic hurricane season
2005 Atlantic hurricane season
The 2005 Atlantic hurricane season was the most active Atlantic hurricane season in recorded history, repeatedly shattering numerous records. The impact of the season was widespread and ruinous with an estimated 3,913 deaths and record damage of about $159.2 billion...
. It formed on August 13 from a tropical wave
Tropical wave
Tropical waves, easterly waves, or tropical easterly waves, also known as African easterly waves in the Atlantic region, are a type of atmospheric trough, an elongated area of relatively low air pressure, oriented north to south, which move from east to west across the tropics causing areas of...
that emerged from the west coast of Africa on August 8. As a result of strong wind shear
Wind shear
Wind shear, sometimes referred to as windshear or wind gradient, is a difference in wind speed and direction over a relatively short distance in the atmosphere...
, the depression remained weak and did not strengthen beyond tropical depression status. The cyclone degenerated on August 14, although its remnants partially contributed to the formation of Tropical Depression Twelve, which eventually intensified into Hurricane Katrina
Hurricane Katrina
Hurricane Katrina of the 2005 Atlantic hurricane season was a powerful Atlantic hurricane. It is the costliest natural disaster, as well as one of the five deadliest hurricanes, in the history of the United States. Among recorded Atlantic hurricanes, it was the sixth strongest overall...
. The cyclone had no effect on land, and did not directly result in any fatalities or damage.
Meteorological history
On August 8, a tropical waveTropical wave
Tropical waves, easterly waves, or tropical easterly waves, also known as African easterly waves in the Atlantic region, are a type of atmospheric trough, an elongated area of relatively low air pressure, oriented north to south, which move from east to west across the tropics causing areas of...
emerged from the west coast of Africa and entered the Atlantic Ocean. Tracking towards the west, the depression began to exhibit signs of convective organization
Atmospheric convection
Atmospheric convection is the result of a parcel-environment instability, or temperature difference, layer in the atmosphere. Different lapse rates within dry and moist air lead to instability. Mixing of air during the day which expands the height of the planetary boundary layer leads to...
on August 11. The system continued to develop, and it is estimated that Tropical Depression Ten formed at 1200 UTC on August 13. At the time, it was located about 1600 miles (2,574.9 km) east of Barbados
Barbados
Barbados is an island country in the Lesser Antilles. It is in length and as much as in width, amounting to . It is situated in the western area of the North Atlantic and 100 kilometres east of the Windward Islands and the Caribbean Sea; therein, it is about east of the islands of Saint...
. Upon its designation, the depression consisted of a large area of thunderstorm activity, with curved banding features and expanding outflow
Outflow (meteorology)
Outflow, in meteorology, is air that flows outwards from a storm system. It is associated with ridging, or anticyclonic flow. In the low levels of the troposphere, outflow radiates from thunderstorms in the form of a wedge of rain-cooled air, which is visible as a thin rope-like cloud on weather...
. However, the environmental conditions were predicted to quickly become unfavorable. The depression moved erratically and slowly towards the west, and wind shear
Wind shear
Wind shear, sometimes referred to as windshear or wind gradient, is a difference in wind speed and direction over a relatively short distance in the atmosphere...
inhabited any significant intensification. Late on August 13, it was "beginning to look like Irene
Hurricane Irene (2005)
Hurricane Irene was a long-lived Cape Verde-type Atlantic hurricane during the 2005 Atlantic hurricane season. The storm formed near Cape Verde on August 4 and crossed the Atlantic, turning northward around Bermuda before becoming extratropical southeast of Newfoundland. Irene persisted for...
-junior as it undergoes southwesterly mid-level shear beneath the otherwise favorable upper-level outflow pattern". The wind shear was expected to relent within 48 hours, prompting some forecast models to suggest the depression would eventually attain hurricane status.
By early August 14, the shear had substantially disrupted the storm, leaving the low-level center of circulation
Atmospheric circulation
Atmospheric circulation is the large-scale movement of air, and the means by which thermal energy is distributed on the surface of the Earth....
exposed from the area of convection, which was also deteriorating. After meandering, the storm began to move westward. Forecasters expected it to resume a northwestward track as high pressure
High pressure area
A high-pressure area is a region where the atmospheric pressure at the surface of the planet is greater than its surrounding environment. Winds within high-pressure areas flow outward due to the higher density air near their center and friction with land...
to the south of Bermuda
Bermuda
Bermuda is a British overseas territory in the North Atlantic Ocean. Located off the east coast of the United States, its nearest landmass is Cape Hatteras, North Carolina, about to the west-northwest. It is about south of Halifax, Nova Scotia, Canada, and northeast of Miami, Florida...
was forecasted to weaken and another high was predicted to form southwest of the Azores
Azores
The Archipelago of the Azores is composed of nine volcanic islands situated in the middle of the North Atlantic Ocean, and is located about west from Lisbon and about east from the east coast of North America. The islands, and their economic exclusion zone, form the Autonomous Region of the...
. By 1800 UTC on August 14, the strong shear had further weakened the storm, and it no longer met the criteria for a tropical cyclone. It degenerated into a remnant low, and the National Hurricane Center issued their final advisory on the cyclone. Moving westward, it occasionally produced bursts of convective activity, before dissipating on August 18.
Tropical Depression Twelve formed over the southeastern Bahamas at 2100 UTC on August 23, partially from the remains of Tropical Depression Ten. While the normal standards for numbering tropical depressions in the Atlantic
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total area of about , it covers approximately 20% of the Earth's surface and about 26% of its water surface area...
stipulate that the initial designation be retained when a depression regenerates, satellite imagery indicated that a second tropical wave
Tropical wave
Tropical waves, easterly waves, or tropical easterly waves, also known as African easterly waves in the Atlantic region, are a type of atmospheric trough, an elongated area of relatively low air pressure, oriented north to south, which move from east to west across the tropics causing areas of...
had combined with Tropical Depression Ten north of Puerto Rico
Puerto Rico
Puerto Rico , officially the Commonwealth of Puerto Rico , is an unincorporated territory of the United States, located in the northeastern Caribbean, east of the Dominican Republic and west of both the United States Virgin Islands and the British Virgin Islands.Puerto Rico comprises an...
to form a new, more complex weather system, which was then designated as Tropical Depression Twelve. In a re-analysis, it was found that the low-level circulation of Tropical Depression Ten had completely detached and dissipated; only the remnant mid-level circulation moved on and merged with the second tropical wave. As a result, the criteria for keeping the same name and identity were not met. Tropical Depression Twelve later became Hurricane Katrina
Hurricane Katrina
Hurricane Katrina of the 2005 Atlantic hurricane season was a powerful Atlantic hurricane. It is the costliest natural disaster, as well as one of the five deadliest hurricanes, in the history of the United States. Among recorded Atlantic hurricanes, it was the sixth strongest overall...
.
Impact
Because Tropical Depression Ten never approached land as a tropical cycloneTropical cyclone
A tropical cyclone is a storm system characterized by a large low-pressure center and numerous thunderstorms that produce strong winds and heavy rain. Tropical cyclones strengthen when water evaporated from the ocean is released as the saturated air rises, resulting in condensation of water vapor...
, no tropical cyclone watches and warnings were issued for any land masses. No effects, damages, or fatalities were reported, and no ships reported tropical storm-force winds in association with the depression. The system did not attain tropical storm status; as such, it was not designated a name by the National Hurricane Center
National Hurricane Center
The National Hurricane Center , located at Florida International University in Miami, Florida, is the division of the National Weather Service responsible for tracking and predicting weather systems within the tropics between the Prime Meridian and the 140th meridian west poleward to the 30th...
. The storm partially contributed to the formation of Hurricane Katrina, which became a Category 5 hurricane on the Saffir-Simpson Hurricane Scale
Saffir-Simpson Hurricane Scale
The Saffir–Simpson Hurricane Scale , or the Saffir–Simpson Hurricane Wind Scale , classifies hurricanes — Western Hemisphere tropical cyclones that exceed the intensities of tropical depressions and tropical storms — into five categories distinguished by the intensities of their sustained winds...
and made landfall in Louisiana
Louisiana
Louisiana is a state located in the southern region of the United States of America. Its capital is Baton Rouge and largest city is New Orleans. Louisiana is the only state in the U.S. with political subdivisions termed parishes, which are local governments equivalent to counties...
, causing catastrophic damage. Katrina was the costliest hurricane, and one of the five deadliest, in the history of the United States.
See also
- Meteorological history of Hurricane KatrinaMeteorological history of Hurricane KatrinaThe meteorological history of Hurricane Katrina, an extremely destructive Category 5 hurricane, began on August 23, 2005 when it originated as Tropical Depression Twelve near the Bahamas. The next day, the tropical depression strengthened to a tropical storm, and was named Katrina; it proceeded to...
- List of storms in the 2005 Atlantic hurricane season
- Timeline of the 2005 Atlantic hurricane seasonTimeline of the 2005 Atlantic hurricane seasonThe timeline of the 2005 Atlantic hurricane season documents the formations, strengthenings, weakenings, landfalls, extratropical transitions, and dissipations of the season's tropical and subtropical storms. The 2005 Atlantic hurricane season was the most active Atlantic hurricane season in...