2000-01 South-West Indian Ocean cyclone season
Encyclopedia
The 2000-01 South-West Indian Ocean
cyclone season was an annual event of tropical cyclone
formation. It started on November 15, 2000 and ended on April 30, 2001. For Mauritius
and the Seychelles
, the season continued until May 15. These dates conventionally delimit the period of each year when most tropical cyclones form in the basin, which is west of 90°E
and south of the Equator
. Tropical cyclones in this basin are monitored by the Regional Specialised Meteorological Centre in Réunion
.
(ITCZ) about 400 km south-west of Diego Garcia
. The Joint Typhoon Warning Center rated the system's potential for development as 'fair' on December 31. After 48 hours of dormancy, the disturbance gradually improved, becoming a tropical storm on January 2. JTWC numbered the system 04S and initiated warnings. At the same time, the Mauritius Meteorological Service upgraded the depression to Tropical Storm Ando.
Over the next 24 hours, the system strengthened rapidly into the first tropical cyclone of the season. By this time the cyclone moved southwestward into a weakness in the subtropical ridge caused by a mid-latitude trough
in the Mozambique Channel
. Ando became an intense cyclone as it passed about 120 km to the south-east of Tromelin Island
, where it brought high gusts to the island. On January 5 Ando's intensity was steady throughout most of the day, but at 1800 UTC, JTWC and MFR estimated different mean wind speeds. Joint Typhoon Warning Center increased their 1-min estimate to 115 kts, while Météo-France lowered their 10-minute estimate to 90 kts. However, MFR increased its estimate once again when Ando reached its maximum peak on January 6.
By January 7, Ando started to weaken under the influence of north-westerly wind shear
. The storm moved southward and dissipated south of Madagascar
on the 13th. Though Ando never made landfall in the inhabited areas of the zone, it brought heavy rains and winds to some countries. As it approached La Reunion
, the storm brought more than 1200 mm of rain and gusts up to 130 km/h. Two people died when they were carried away by flood waters. As a developing storm, Ando produced some heavy rain between December 30 and January 2 over the Seychelles
. Swaziland
also reported that Ando drew moisture from the continent, aggravating a persistent dry spell.
. A weak low moved westward, crossing longitude 90°E
on January 3. After traveling three days and more than 1000 km, the system entered an area with less vertical shear. The JTWC upgraded the system's development potential to 'fair' and issued two Formation Alerts before MFR upgraded the disturbance to a tropical depression on January 7.
The following night, after reaching the tropical storm stage, the system was named Bindu by the TCWC in Mauritius
. Bindu began tracking southward towards a weakness in the pressure field induced by a mid-level ridge. This track brought the storm closer to an upper level ridge near 15°S
where conditions were favorable for development. Between the 8th and 9th, Bindu became a very small tropical cyclone: the CDO, which surrounded a 25 km diameter eye, had a diameter of about 100 km. Having entered a region of weak steering flow, the cyclone became quasistationary and weakened back to a tropical storm because of energy overconsumption.
During the evening of the 10th, Bindu moved west-south-west under the influence of a steering current. In response to this movement, the system reintensified until it reached its peak intensity on January 12. The cyclone maintained its strength as it moved east of Rodrigues
, but started to weaken the next day due to the intrusion of dry air and shear. The storm turned south and became extratropical on the 18th near latitude 30°S
. Bindu tracked far from any islands, and did not influence their weather.
. The system was poorly-organized and development was slow until it drifted west of 90°E
on January 16. Météo-France issued their first bulletin on Tropical Disturbance 05 at 1800 UTC the next day. Joint Typhoon Warning Center issued a formation alert on the 18th and numbered the system 06S. On January 19, Mauritius TCWC upgraded the depression to a tropical storm and assigned the name Charly.
From then on, the storm steadily intensified to become the second intense tropical cyclone of the season. A ragged eye developed in the morning of January 20 while Charly was still a tropical storm. Intensification was more vigorous the next day when the cyclone deepened by about 35 hPa
in 24 hours. Charly reached its peak intensity late in the afternoon on January 22 when it was centered approximately 900 km east of Rodrigues. Along with Ando, it was one of two intense cyclones to develop during the season. Different versions of the MFR best track conflict over which of the two cyclones was more intense.
Before reaching peak intensity, Charly was tracking along a high level ridge; but when it approached latitude 20°S
, the storm was on the polar side of that ridge under strong vertical shear. At the same time, the cyclone struggled with dry air and cold waters. On January 29, Charly was an extratropical cyclone.
. The depression drifted erratically for a couple of days and then moved west-southwestward towards the southeastern coastal regions of the country to where it dissipated on the 24th. La Reunion estimated the storm's maximum sustained winds at 55 km/h, while the Joint Typhoon Warning Center never issued any warnings.
into less favorable waters. It passed about 325 nmi east of Rodrigues before becoming extratropical on the 3rd. The storm had a large circulation, with 30 knot winds extending about 250-300 nmi southeast of the center. The JTWC issued another Formation Alert on 2 February, but did not issue any warnings on the depression. (In the Southern Hemisphere JTWC usually does not initiate warnings until winds have reached 35 kts.)
, then the Sub-regional Tropical Cyclone Advisory Centre in Madagascar
assigns the appropriate name to the storm. If a tropical disturbance reaches moderate tropical storm status between 55°E
and 90°E
, then the Sub-regional Tropical Cyclone Advisory Centre in Mauritius
assigns the appropriate name to the storm. A new annual list is used every year so no names are retired.
Indian Ocean
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...
cyclone season was an annual event of tropical cyclone
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...
formation. It started on November 15, 2000 and ended on April 30, 2001. For Mauritius
Mauritius
Mauritius , officially the Republic of Mauritius is an island nation off the southeast coast of the African continent in the southwest Indian Ocean, about east of Madagascar...
and the Seychelles
Seychelles
Seychelles , officially the Republic of Seychelles , is an island country spanning an archipelago of 115 islands in the Indian Ocean, some east of mainland Africa, northeast of the island of Madagascar....
, the season continued until May 15. These dates conventionally delimit the period of each year when most tropical cyclones form in the basin, which is west of 90°E
90th meridian east
The meridian 90° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Asia, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole.The Ninety East Ridge is named after the meridian....
and south of the Equator
Equator
An equator is the intersection of a sphere's surface with the plane perpendicular to the sphere's axis of rotation and containing the sphere's center of mass....
. Tropical cyclones in this basin are monitored by the Regional Specialised Meteorological Centre in Réunion
Réunion
Réunion is a French island with a population of about 800,000 located in the Indian Ocean, east of Madagascar, about south west of Mauritius, the nearest island.Administratively, Réunion is one of the overseas departments of France...
.
Tropical Depression 01
This storm existed from August 1 until August 3. It was also classified as Tropical Cyclone 01S by the Joint Typhoon Warning Center.Tropical Depression 02
This storm existed from November 12 until November 18. It was also classified as Tropical Cyclone 02S by the Joint Typhoon Warning Center.Intense Tropical Cyclone Ando
The beginnings of Ando can be traced to an area of convection within the Intertropical Convergence ZoneIntertropical Convergence Zone
The Intertropical Convergence Zone , known by sailors as The Doldrums, is the area encircling the earth near the equator where winds originating in the northern and southern hemispheres come together....
(ITCZ) about 400 km south-west of Diego Garcia
Diego Garcia
Diego Garcia is a tropical, footprint-shaped coral atoll located south of the equator in the central Indian Ocean at 7 degrees, 26 minutes south latitude. It is part of the British Indian Ocean Territory [BIOT] and is positioned at 72°23' east longitude....
. The Joint Typhoon Warning Center rated the system's potential for development as 'fair' on December 31. After 48 hours of dormancy, the disturbance gradually improved, becoming a tropical storm on January 2. JTWC numbered the system 04S and initiated warnings. At the same time, the Mauritius Meteorological Service upgraded the depression to Tropical Storm Ando.
Over the next 24 hours, the system strengthened rapidly into the first tropical cyclone of the season. By this time the cyclone moved southwestward into a weakness in the subtropical ridge caused by a mid-latitude trough
Trough (meteorology)
A trough is an elongated region of relatively low atmospheric pressure, often associated with fronts.Unlike fronts, there is not a universal symbol for a trough on a weather chart. The weather charts in some countries or regions mark troughs by a line. In the United States, a trough may be marked...
in the Mozambique Channel
Mozambique Channel
The Mozambique Channel is a portion of the Indian Ocean located between the island nation of Madagascar and southeast Africa, primarily the country of Mozambique. It was a World War II clashpoint during the Battle of Madagascar...
. Ando became an intense cyclone as it passed about 120 km to the south-east of Tromelin Island
Tromelin Island
Tromelin Island is a low, flat 0.8-square-kilometre island in the Indian Ocean, about east of Madagascar . There are no harbours or anchorages and access by sea is difficult. The island has a 1,200-metre airstrip. It is a French territory...
, where it brought high gusts to the island. On January 5 Ando's intensity was steady throughout most of the day, but at 1800 UTC, JTWC and MFR estimated different mean wind speeds. Joint Typhoon Warning Center increased their 1-min estimate to 115 kts, while Météo-France lowered their 10-minute estimate to 90 kts. However, MFR increased its estimate once again when Ando reached its maximum peak on January 6.
By January 7, Ando started to weaken under the influence of north-westerly 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 storm moved southward and dissipated south of Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
on the 13th. Though Ando never made landfall in the inhabited areas of the zone, it brought heavy rains and winds to some countries. As it approached La Reunion
La Reunion
La Reunion may refer to:* La Reunion , a communal settlement near present-day Dallas, Texas*La Réunion, Lot-et-Garonne, a town in the Lot-et-Garonne department of France*Réunion, an island in the Indian Ocean east of Madagascar...
, the storm brought more than 1200 mm of rain and gusts up to 130 km/h. Two people died when they were carried away by flood waters. As a developing storm, Ando produced some heavy rain between December 30 and January 2 over the Seychelles
Seychelles
Seychelles , officially the Republic of Seychelles , is an island country spanning an archipelago of 115 islands in the Indian Ocean, some east of mainland Africa, northeast of the island of Madagascar....
. Swaziland
Swaziland
Swaziland, officially the Kingdom of Swaziland , and sometimes called Ngwane or Swatini, is a landlocked country in Southern Africa, bordered to the north, south and west by South Africa, and to the east by Mozambique...
also reported that Ando drew moisture from the continent, aggravating a persistent dry spell.
Tropical Cyclone Bindu
When Ando became a named tropical storm, the second system formed in the monsoon trough north of Cocos IslandCocos (Keeling) Islands
The Territory of the Cocos Islands, also called Cocos Islands and Keeling Islands, is a territory of Australia, located in the Indian Ocean, southwest of Christmas Island and approximately midway between Australia and Sri Lanka....
. A weak low moved westward, crossing longitude 90°E
90th meridian east
The meridian 90° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Asia, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole.The Ninety East Ridge is named after the meridian....
on January 3. After traveling three days and more than 1000 km, the system entered an area with less vertical shear. The JTWC upgraded the system's development potential to 'fair' and issued two Formation Alerts before MFR upgraded the disturbance to a tropical depression on January 7.
The following night, after reaching the tropical storm stage, the system was named Bindu by the TCWC in Mauritius
Mauritius
Mauritius , officially the Republic of Mauritius is an island nation off the southeast coast of the African continent in the southwest Indian Ocean, about east of Madagascar...
. Bindu began tracking southward towards a weakness in the pressure field induced by a mid-level ridge. This track brought the storm closer to an upper level ridge near 15°S
15th parallel south
The 15th parallel south is a circle of latitude that is 15 degrees south of the Earth's equatorial plane. It crosses the Atlantic Ocean, Africa, the Indian Ocean, Australasia, the Pacific Ocean and South America....
where conditions were favorable for development. Between the 8th and 9th, Bindu became a very small tropical cyclone: the CDO, which surrounded a 25 km diameter eye, had a diameter of about 100 km. Having entered a region of weak steering flow, the cyclone became quasistationary and weakened back to a tropical storm because of energy overconsumption.
During the evening of the 10th, Bindu moved west-south-west under the influence of a steering current. In response to this movement, the system reintensified until it reached its peak intensity on January 12. The cyclone maintained its strength as it moved east of Rodrigues
Rodrigues (island)
Rodrigues , sometimes spelled Rodriguez but named after the Portuguese explorer Diogo Rodrigues, is the smallest of the Mascarene Islands and a dependency of Mauritius...
, but started to weaken the next day due to the intrusion of dry air and shear. The storm turned south and became extratropical on the 18th near latitude 30°S
30th parallel south
The 30th parallel south is a circle of latitude that is 30 degrees south of the Earth's equatorial plane. It crosses the Atlantic Ocean, Africa, the Indian Ocean, Australasia, the Pacific Ocean and South America....
. Bindu tracked far from any islands, and did not influence their weather.
Intense Tropical Cyclone Charly
During the second week of January another disturbance developed in the South-East Indian Ocean approximately 600 km southwest of SumatraSumatra
Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...
. The system was poorly-organized and development was slow until it drifted west of 90°E
90th meridian east
The meridian 90° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Asia, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole.The Ninety East Ridge is named after the meridian....
on January 16. Météo-France issued their first bulletin on Tropical Disturbance 05 at 1800 UTC the next day. Joint Typhoon Warning Center issued a formation alert on the 18th and numbered the system 06S. On January 19, Mauritius TCWC upgraded the depression to a tropical storm and assigned the name Charly.
From then on, the storm steadily intensified to become the second intense tropical cyclone of the season. A ragged eye developed in the morning of January 20 while Charly was still a tropical storm. Intensification was more vigorous the next day when the cyclone deepened by about 35 hPa
HPA
-Organizations:*Halifax Port Authority, a port authority in Canada*Hamburg Port Authority, the port authority for the Port of Hamburg, Germany*Health Protection Agency, a health organization in the United Kingdom...
in 24 hours. Charly reached its peak intensity late in the afternoon on January 22 when it was centered approximately 900 km east of Rodrigues. Along with Ando, it was one of two intense cyclones to develop during the season. Different versions of the MFR best track conflict over which of the two cyclones was more intense.
Before reaching peak intensity, Charly was tracking along a high level ridge; but when it approached latitude 20°S
20th parallel south
The 20th parallel south is a circle of latitude that is 20 degrees south of the Earth's equatorial plane. It crosses the Atlantic Ocean, Africa, the Indian Ocean, Australasia, the Pacific Ocean and South America....
, the storm was on the polar side of that ridge under strong vertical shear. At the same time, the cyclone struggled with dry air and cold waters. On January 29, Charly was an extratropical cyclone.
Tropical Depression 06
While Intense Tropical Cyclone Charly was spinning to the east of Mauritius, another system was forming off the east coast of central Madagascar. On 22 January, Météo-France issued the first bulletin on the disturbance. Later that day the system strengthened into a depression - eventually peaking at an intensity of 997 hPaPascal (unit)
The pascal is the SI derived unit of pressure, internal pressure, stress, Young's modulus and tensile strength, named after the French mathematician, physicist, inventor, writer, and philosopher Blaise Pascal. It is a measure of force per unit area, defined as one newton per square metre...
. The depression drifted erratically for a couple of days and then moved west-southwestward towards the southeastern coastal regions of the country to where it dissipated on the 24th. La Reunion estimated the storm's maximum sustained winds at 55 km/h, while the Joint Typhoon Warning Center never issued any warnings.
Tropical Depression 07
The only system in the region during the month of February was Tropical Depression 07. Late on 31 January, the Joint Typhoon Warning Center issued a Formation Alert, indicating a weak circulation was located about 450 nmi northeast of Rodrigues Island. Météo-France issued the first tropical disturbance bulletin at 0600 UTC 1 February, designating the system as Tropical Disturbance 07. The disturbance was upgraded to a tropical depression six hours later when its central winds were estimated at about 55 km/h. The depression generally moved on a southerly course, taking it away of the tropicsTropics
The tropics is a region of the Earth surrounding the Equator. It is limited in latitude by the Tropic of Cancer in the northern hemisphere at approximately N and the Tropic of Capricorn in the southern hemisphere at S; these latitudes correspond to the axial tilt of the Earth...
into less favorable waters. It passed about 325 nmi east of Rodrigues before becoming extratropical on the 3rd. The storm had a large circulation, with 30 knot winds extending about 250-300 nmi southeast of the center. The JTWC issued another Formation Alert on 2 February, but did not issue any warnings on the depression. (In the Southern Hemisphere JTWC usually does not initiate warnings until winds have reached 35 kts.)
Tropical Depression 10
This compact system existed from April 3 until April 5. It was also classified as Tropical Cyclone 16S by the Joint Typhoon Warning Center.Storm names
A tropical disturbance is named when it reaches moderate tropical storm strength. If a tropical disturbance reaches moderate tropical storm status west of 55°E55th meridian east
The meridian 55° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Europe, Asia, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole....
, then the Sub-regional Tropical Cyclone Advisory Centre in Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
assigns the appropriate name to the storm. If a tropical disturbance reaches moderate tropical storm status between 55°E
55th meridian east
The meridian 55° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Europe, Asia, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole....
and 90°E
90th meridian east
The meridian 90° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Asia, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole.The Ninety East Ridge is named after the meridian....
, then the Sub-regional Tropical Cyclone Advisory Centre in Mauritius
Mauritius
Mauritius , officially the Republic of Mauritius is an island nation off the southeast coast of the African continent in the southwest Indian Ocean, about east of Madagascar...
assigns the appropriate name to the storm. A new annual list is used every year so no names are retired.
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See also
- List of Southern Hemisphere tropical cyclone seasons
- Atlantic hurricane seasons: 20002000 Atlantic hurricane seasonThe 2000 Atlantic hurricane season was the first season without a tropical cyclone in July since 1987. The season officially began on June 1, 2000, and lasted until November 30, 2000. The June through November dates conventionally delimit the period of each year when most tropical cyclones form in...
, 20012001 Atlantic hurricane seasonThe 2001 Atlantic hurricane season was a fairly active Atlantic hurricane season that produced 17 tropical cyclones, 15 named storms, nine hurricanes, and four major hurricanes. The season officially lasted from June 1, 2001, to November 30, 2001, dates which by convention limit the period of each... - Pacific hurricane seasons: 20002000 Pacific hurricane seasonThe 2000 Pacific hurricane season was an event in tropical cyclone meteorology. There were few notable storms this year. Tropical Storms Miriam, Norman, and Rosa all made landfall in Mexico with minimal impact. Hurricane Daniel briefly threatened the U.S. state of Hawaii while weakening...
, 20012001 Pacific hurricane seasonThe 2001 Pacific hurricane season was an event in tropical cyclone meteorology. The most notable storm that year was Hurricane Juliette, which caused devastating floods in Baja California, leading to 12 fatalities and $400 million worth of damage... - Pacific typhoon seasons: 20002000 Pacific typhoon seasonThe 2000 Pacific typhoon season has no official bounds; it ran year-round in 2000, but most tropical cyclones tend to form in the northwestern Pacific Ocean between May and November...
, 20012001 Pacific typhoon seasonThe 2001 Pacific typhoon season has no official bounds; it ran year-round in 2001, but most tropical cyclones tend to form in the northwestern Pacific Ocean between May and November... - North Indian Ocean cyclone seasons: 20002000 North Indian Ocean cyclone seasonThe 2000 North Indian Ocean cyclone season had no bounds, but cyclones tend to form between April and December, with peaks in May and November. These dates conventionally delimit the period of each year when most tropical cyclones form in the northern Indian Ocean.-Season summary:Six tropical...
, 20012001 North Indian Ocean cyclone seasonThe 2001 North Indian Ocean cyclone season had no bounds, but cyclones tend to form between April and December, with peaks in May and November. These dates conventionally delimit the period of each year when most tropical cyclones form in the northern Indian Ocean.-Season summary:Four tropical...
External links
- Joint Typhoon Warning Center (JTWC).
- Météo France (RSMC La Réunion).
- World Meteorological Organization
- WMO Annual Summary of Global Tropical Cyclone Seasons 2000
- WMO Annual Summary of Global Tropical Cyclone Seasons 2001
- RA I Tropical Cyclone Committee Final Report
- Joint Typhoon Warning Center 2001 ATCR
- 2000-01 Best Track Data from Météo France
- 2000-2001 Season Summary from Météo France
- July 2000 to June 2001 Tropical Cyclone Summaries and Operational Track Data
- Gary Padgett's Southern Hemisphere 2000-2001 Tropical Cyclone Season Review
- Report on Tropical Cyclone Ando