Meteorological history | |
---|---|
Formed | January 18,1991 |
Dissipated | February 4,1991 |
Intense tropical cyclone | |
10-minute sustained (MFR) | |
Highest winds | 215 km/h (130 mph) |
Lowest pressure | 915 hPa (mbar);27.02 inHg |
Category 4-equivalent tropical cyclone | |
1-minute sustained (SSHWS/JTWC) | |
Highest winds | 240 km/h (150 mph) |
Overall effects | |
Missing | 36 |
Areas affected | Rodrigues,Mauritius,Réunion |
IBTrACS | |
Part of the 1990–91 South-West Indian Ocean cyclone season |
Intense Tropical Cyclone Bella was a destructive tropical cyclone that passed near the Mauritius outer island of Rodrigues. The second named storm of the season,Bella originated in the middle of January 1991 from a surge in the monsoon trough to the southwest of Sumatra. For several days,the system remained weak as it moved generally west-southwestward. On January 25,it intensified to tropical storm status,but Bella took three more days to intensify to tropical cyclone status,with 10 minute maximum sustained winds of 120 kilometres per hour (75 miles per hour). The cyclone attained peak intensity on January 29,officially reaching winds of 155 km/h (95 mph). The Joint Typhoon Warning Center unofficially estimated winds of 240 km/h (150 mph),the highest the agency estimated for any storm in the Southern Hemisphere in the year. Bella later turned to the southeast and weakened,passing about 50 km (30 mi) west of Rodrigues on January 31. The storm turned to the south-southwest and back to the southeast again,becoming extratropical on February 4.
While passing near Rodrigues,Bella produced strong winds and high tides,the latter of which caused flooding in the capital Port Mathurin. The storm was considered the worst on the island in 20 years. About 1,500 homes were damaged or destroyed,leaving 1,000 people homeless. Bella also severely damaged crops,roads,and the power grid on Rodrigues. The storm killed about half of the Rodrigues flying fox,a critically endangered species. Elsewhere,Bella was believed to have sunk a Madagascar cargo ship,with its 36 people on board.
Similar to Cyclone Alison that had formed in early January 1991, a surge in the monsoon trough spawned what would become Tropical Cyclone Bella, associated with the Intertropical Convergence Zone. [1] [2] On January 13, the Joint Typhoon Warning Center (JTWC) [nb 1] began monitoring a system about 660 km (410 mi) southwest of Padang, Sumatra in the Australian basin. Moving to the west-southwest, the system crossed into the south-west Indian Ocean on January 17, and the next day was tracked by the Météo France office in Réunion (MFR). [nb 2] On January 20, the disturbance turned sharply to the south-southeast, although its westward motion resumed late the following day, [5] influenced by a ridge to the south. [1]
On January 22, the disturbance intensified into a tropical depression. [5] The JTWC upgraded the storm to tropical storm status on January 23, three days after classifying it as Tropical Cyclone 08S. [6] [5] On January 25, the MFR upgraded the depression to Tropical Storm Bella, a week after beginning to issue advisories. Around that time, the storm became visible on MFR satellite imagery. [5] [2] Following a lengthy period of minimal development, Bella subsequently intensified at a more regular rate as it slowed its forward motion. On January 26, it turned more to the southwest, but the westward track resumed on the next day. [5] Aided by warm sea surface temperatures of 28 °C (82 °F), Bella began to intensify quickly. [2] On January 28, both the JTWC and the MFR upgraded the storm to the equivalent of a minimal hurricane, estimating winds of 120 km/h (75 mph); this made Bella a tropical cyclone, the first of the season. [5] Around this time, the storm developed a well-defined eye 60 km (35 mi) in diameter. [2]
After becoming a tropical cyclone, Bella continued to intensify, reaching peak winds on January 29. The MFR estimated 10 minute winds of 155 km/h (95 mph), and assessed a barometric pressure of 936 mbar (27.6 inHg) at that time. Meanwhile, the JTWC estimated 1 minute peak winds of 240 km/h (150 mph); [5] this strength, equivalent to a super typhoon, was the highest the JTWC estimated for any Southern Hemisphere storm during the tropical cyclone year. [6] On January 30, Bella turned to the southeast and began weakening, [5] affected by wind shear in the region. [1] The cyclone passed about 50 km (30 mi) west of Rodrigues at 03:00 UTC on January 31, [2] with 10 minute winds of 135 km/h (85 mph). Shortly thereafter, the cyclone deteriorated into a tropical storm. The southeast trajectory was short-lived, as Bella turned more to the south-southwest on February 1. [5] After a final turn to the southeast, Bella became an extratropical cyclone on February 4. [2]
Before Bella affected land, a class one warning, the lowest of four, was issued for Réunion, while a class four warning was issued for Rodrigues. [7]
While moving near Rodrigues, Bella produced wind gusts of 210 km/h (130 mph), [8] along with high tides that flooded the northern coastline, including the capital Port Mathurin. [2] The storm damaged 1,200 homes and destroyed 300 others, [8] leaving about 1,000 people homeless. [2] About 30 schools were wrecked. The storm damaged about 75% of the electrical network was damaged, which also disrupted water supply on the island, and about 30% of roads were damaged. [2] Over 90% of the crops on the island were destroyed, [2] with many livestock killed. [8] Cyclone Bella killed about half of the Rodrigues flying fox, a critically endangered species, decreasing the numbers from around 800 to around 400. The species had regrown from a minimum of around 70 in 1971, and the trend toward regrowth continued after the storm, reaching about 3,500 in 2002. The storm also affected the Rodrigues warbler. [9] The storm also injured nine people, [2] and overall, Bella was considered the worst storm on the island in 20 years. [10]
A 16,570 ton cargo ship traveling from Madagascar to Réunion was lost on January 30 about 700 km (430 mi) to the south of the center of Bella. The ship likely sank due to the cyclone, with 36 people on board. [2]
In the aftermath of the storm, seven people contracted Typhoid fever on Rodrigues in relation to the storm. [2] After Bella passed, the government of Mauritius noted the need for 4,500 m (15,000 ft) of galvanized pipes to assist in rebuilding, as well as generators. [8] The United States Agency for International Development donated $25,000 (1991 USD) to Mauritius to help in the aftermath. France, the United Kingdom, and India also donated to the country. [11]
The 1995–96 South-West Indian Ocean cyclone season was a moderately active season that included Cyclone Bonita, which was the first known tropical cyclone to cross from the southern Indian Ocean into the southern Atlantic Ocean. Tropical activity lasted for about six months from the middle of November 1995 to early May 1996. The first storm, Intense Tropical Cyclone Agnielle, formed in the adjacent Australian basin on November 16 and later reached peak winds in the south-west Indian Ocean. The next named storm after Agnielle was Bonita, which formed in early January and killed 42 people. The basin was most active in February, with two tropical cyclones, or the equivalent of a minimal hurricane, as well as a severe tropical storm. The first of these three was Doloresse, which killed 67 people due to a shipwreck in the Comoros. The next storm was Cyclone Edwige, which caused heavy crop damage on Mauritius before looping along the east coast of Madagascar. In March, both Cyclone Flossy and Tropical Storm Guylianne passed near the Mascarene Islands, producing heavy rainfall and gusty winds.
The 2006–07 South-West Indian Ocean cyclone season featured the second-most intense tropical cyclones for a season in the tropical cyclone basin, only behind the 2018–19 season. The basin contains the waters of the Indian Ocean south of the equator and west of 90°E. Météo-France's meteorological office in Réunion (MFR), the official Regional Specialized Meteorological Center for the South-West Indian Ocean, tracked 15 tropical disturbances, of which eleven attained gale-force winds. The season began in October 2006 with a short-lived tropical disturbance, followed by Anita in November, which was the first named storm of the season. Cyclone Bondo was the first of six intense tropical cyclones, which took a rare track through the southern Seychelles before making landfall on northwest Madagascar, killing 11 people. Severe Tropical Storm Clovis lasted from December 2006 to January 2007; it struck eastern Madagascar, killing four people.
The 2004–05 South-West Indian Ocean cyclone season was a near average season, despite beginning unusually early on August 30 with the formation of an early-season tropical depression. Météo-France's meteorological office in Réunion (MFR) ultimately monitored 18 tropical disturbances during the season, of which 15 became tropical depressions. Two storms – Arola and Bento – formed in November, and the latter became the most intense November cyclone on record. Bento attained its peak intensity at a low latitude, and weakened before threatening land. Tropical Cyclone Chambo was the only named storm in December. In January, Severe Tropical Storm Daren and Cyclone Ernest existed simultaneously. The latter storm struck southern Madagascar, and five days later, Moderate Tropical Storm Felapi affected the same area; the two storms killed 78 people and left over 32,000 people homeless. At the end of January, Severe Tropical Storm Gerard existed as an unnamed tropical storm for 18 hours due to discrepancies between warning centers.
The 2003–04 South-West Indian Ocean cyclone season featured the most intense tropical cyclone in the South-West Indian Ocean, Cyclone Gafilo, as well as nine other named storms. Tropical activity began on September 28 when Moderate Tropical Storm Abaimba formed at a low latitude. Activity continued until late May, following Severe Tropical Storm Juba, which marked the third year in a row that a storm formed in May. The final disturbance, one of sixteen, dissipated on May 24. Activity was near average, and the season was one of the longest on record.
The 2002–03 South-West Indian Ocean cyclone season was one of the longest lasting and the third-most active season in the South-West Indian Ocean. Storms during the season impacted the Mascarene Islands, Seychelles, Madagascar, and countries in south-eastern Africa. The season began early when an unnamed tropical storm struck Seychelles in September, becoming the most damaging storm there in 50 years. The next system, Atang, was the first named storm of the season, but was only a tropical depression; it was named due to the threat to an outer island of Mauritius. Atang later struck Tanzania in a climatologically unusual area in November, resulting in unconfirmed deaths of fishermen. The first named storm to reach tropical storm intensity was Boura, which brushed the Mascarene Islands with gusty winds and rainfall. In December, Cyclone Crystal threatened to strike Mauritius but instead veered eastward, and later, Tropical Storm Delfina lasted from late December through early January 2003. Delfina damaged or destroyed thousands of houses in Mozambique and Malawi, killing 54 people.
The 2001–02 South-West Indian Ocean cyclone season had the earliest named storm since 1992. Many storms formed in the north-east portion of the basin, and several more originated around Australia. The basin is defined as the waters of the Indian Ocean west of longitude 90°E to the coast of Africa and south of the equator. Eleven tropical storms formed, compared to an average of nine. Tropical systems were present during 73 days, which was significantly higher than the average of 58 for this basin.
The 1998–99 South-West Indian Ocean cyclone season was a quiet season that had the fourth-lowest number of days with tropical storm or tropical cyclone activity. Most of the storms formed either in the Mozambique Channel or in the far eastern portion of the basin, with five storms crossing from the adjacent Australian basin east of 90° E. As a result, few storms impacted Madagascar, and none made landfall on the African continent. Throughout most of the season, there was below-normal sea surface temperatures in the Indian Ocean east of Madagascar. In February, typically the peak in activity, Réunion island recorded its highest average monthly pressure since 1953. Due to generally unfavorable conditions, there were only six tropical storms tracked by the Météo-France office (MFR) on Réunion. There were only two tropical cyclones – a storm with winds of at least 120 km/h (75 mph).
Intense Tropical Cyclone Kalunde was the strongest storm of the 2002–03 South-West Indian Ocean cyclone season. The eleventh named storm and sixth cyclone of the season, Kalunde formed on March 4 from an area of disturbed weather east-southeast of Diego Garcia. The storm steadily strengthened and attained severe tropical storm intensity on March 6. After starting a phase of rapid deepening, Kalunde attained cyclone intensity the next day. Kalunde attained its peak intensity on March 8, as an intense tropical cyclone. It maintained its peak strength for a day; shortly thereafter, the system began to weaken. After undergoing an eyewall replacement cycle, the storm brushed Rodrigues. Shortly after doing so, Kalunde weakened into a tropical cyclone and later a severe tropical storm. Two days later, on March 16, the cyclone transitioned into an extratropical cyclone and dissipated the next day.
The 1990–91 South-West Indian Ocean cyclone season was fairly quiet, although activity began early and the final named storm formed at a record late date. There were seven named storms classified by the Météo-France office (MFR) on Réunion, as well as three depressions; an additional depression was classified by the Joint Typhoon Warning Center (JTWC), an unofficial warning agency. The JTWC tracked storms in both September and October, although neither affected land. In late November, another short-lived depression formed in the northeastern portion of the basin. Activity remained minimal until January, when Tropical Storm Alison formed in the eastern portion of the basin. Later in the month, Cyclone Bella became the strongest storm of the season, reaching 10‑minute maximum sustained winds of 155 km/h (96 mph). It passed near the island of Rodrigues, becoming the worst cyclone there in 20 years and killing half of the population of one endangered species. Bella also likely caused a cargo ship to go missing with 36 people on board. Three storms developed in short succession in the second half of February. Cyclone Cynthia developed rapidly in the Mozambique Channel on February 16 and struck western Madagascar, killing 36 people and ruining local rice harvests. A residual trough after Cynthia dissipated spawned Tropical Storm Debra, which looped in the Mozambique Channel. Toward the end of the month, Tropical Storm Elma exited the basin into the adjacent Australian region, only to re-enter the south-west Indian Ocean and dissipate. Long-lived Cyclone Fatima originated in the Australian basin in late March and changed directions before becoming extratropical. On April 2, a tropical depression struck eastern Madagascar, killing 18 people. The final storm, Gritelle, was named on June 10, the latest on record.
The 1991–92 South-West Indian Ocean cyclone season was an average cyclone season in which most storms remained over open waters. At the time, the season's official bounds lasted from November 15, 1991, to April 30, 1992, although this season began early when three tropical depressions formed before the official start. The second, designated Tropical Depression A2 by the Météo-France office (MFR) on Réunion, passed north of Madagascar on October 16 before weakening.
The 1992–93 South-West Indian Ocean cyclone season lasted longer than normal, with the first storm Aviona forming on September 27 and the final storm Konita not dissipating until May 7. It was an above-average season, with four tropical cyclones – the equivalent of a minimal hurricane – along with six tropical storms, one subtropical depression, and several depressions including one that was named. The basin is defined as the area west of 90°E and south of the Equator in the Indian Ocean, which includes the waters around Madagascar westward to the east coast of Africa. Tropical cyclones in this basin are monitored by the Regional Specialised Meteorological Centre in Réunion (MFR), as well as by the Joint Typhoon Warning Center (JTWC).
The 1982–83 South-West Indian Ocean cyclone season was the least active cyclone season in the basin since 1961–1962. There were six systems that were named, although three of them – Arilisy, Clera, and Fely – failed to intensify beyond tropical depression status. No storms reached tropical cyclone status, according to the official warning agency for the basin, Météo-France, although the two strongest storms – Bemany and Elinah – peaked just below that intensity. The first named storm, Arilisy, formed on October 27, and dissipated without having affected land. However, the Joint Typhoon Warning Center (JTWC), which is an unofficial warning center for the basin, briefly tracked a tropical depression in July. The next storm was Bemany, which passed east of Mauritius near peak intensity in early December. Tropical Depression Clera existed briefly in the middle of September, and Tropical Storm Dadafy moved across the eastern portion of the basin in late December.
The 1983–84 South-West Indian Ocean cyclone season featured above normal activity and several deadly storms. There was steady storm activity from December through April due to favorable conditions, such as warm sea surface temperatures and an active monsoon. The first named storm – Andry – was tied for the strongest with Bakoly, Jaminy, and Kamisy. Cyclone Andry passed near Agaléga island within Mauritius, damaging or destroying every building there and killing one person. It later struck Madagascar, the first of three storms to strike the nation within two months, which collectively caused $25 million in damage and 42 deaths. The third of these storms, Tropical Storm Domoina, caused deadly flooding in southeastern Africa that killed 242 people and caused $199 million in damage. The storm destroyed more than 50 small dams in Madagascar and caused the worst flooding in Swaziland in 20 years. In addition three of the first storms affecting Madagascar, Cyclone Bakoly in December left $21 million in damage on Mauritius.
The 1989–90 South-West Indian Ocean cyclone season was an average cyclone season, with nine named storms and five tropical cyclones – a storm attaining maximum sustained winds of at least 120 km/h (75 mph). The season officially ran from November 1, 1989, to April 30, 1990. Storms were officially tracked by the Météo-France office (MFR) on Réunion while the Joint Typhoon Warning Center (JTWC) in an unofficial basis. The first storm, Cyclone Alibera, was the second longest-lasting tropical cyclone on record in the basin, with a duration of 22 days. Alibera meandered and changed directions several times before striking southeastern Madagascar on January 1, 1989, where it was considered the worst storm since 1925. The cyclone killed 46 people and left widespread damage. Only the final storm of the year – Severe Tropical Storm Ikonjo – also had significant impact on land, when it left $1.5 million in damage (1990 USD) in the Seychelles.
The 1988–89 South-West Indian Ocean cyclone season was an active season that featured several storms moving near or over the Mascarene Islands or Madagascar. The eleven tropical storms was two greater than average, of which five became tropical cyclones – a storm with maximum sustained winds over 10 minutes of 120 km/h (75 mph) or greater. Storms were monitored by the Météo-France office (MFR) on Réunion island in an official capacity, as well as the American Joint Typhoon Warning Center (JTWC) on an unofficial base. The season began early with Moderate Tropical Storm Adelinina forming in early November, and continued through the middle of April. Adelinina was one of two storms to form in November, the other being Tropical Cyclone Barisaona which crossed from the adjacent Australian basin.
The 1986–87 South-West Indian Ocean cyclone season was below average due to an ongoing El Niño and a weak monsoon that suppressed convection and storms. There were only five named storms tracked by the Météo-France office (MFR) on Réunion. The United States-based Joint Typhoon Warning Center (JTWC) followed four other storms in the basin, which is the waters of the Indian Ocean south of the equator and west of 90° E to the coast of Africa. The JTWC tracked a storm on August 1 in the northeastern portion of the basin, unusual for the time of year. The first named storm was Severe Tropical Storm Alinina, which originated from the Intertropical Convergence Zone east of Madagascar in the middle of January. However, there was an unnamed tropical depression that produced heavy rainfall in Réunion and Madagascar, causing two deaths in the latter country.
The 1985–86 South-West Indian Ocean cyclone season was the first in which the Météo-France office (MFR) on Réunion tracked cyclones as far east as 90° E in Indian Ocean, south of the equator. Previously, the agency's area of responsibility was limited to 80° E. It was an active season with twelve named storms, of which five strengthened into tropical cyclone with 10 minute sustained winds of at least 120 km/h (75 mph). The first named storm was Tropical Storm Alifredy, which originated in the Mozambique Channel in late December and moved across Madagascar. However, the unofficial Joint Typhoon Warning Center (JTWC) tracked a short-lived storm in September.
The 1993–94 South-West Indian Ocean cyclone season was the most active season in the basin since the start of reliable satellite coverage in 1967, until the record was surpassed 25 years later in the 2018–19 South-West Indian Ocean cyclone season. Activity lasted from mid-November, when Moderate Tropical Storm Alexina formed, until mid-April, when Tropical Cyclone Odille became extratropical. Four tropical cyclones – Daisy, Geralda, Litanne, and Nadia – struck eastern Madagascar, of which Geralda was the costliest and deadliest. With gusts as strong as 350 km/h (215 mph) accompanied by heavy rainfall, Geralda destroyed more than 40,000 homes and left 356,000 people homeless. Geralda killed 231 people and caused more than $10 million in damage. Cyclone Nadia was the second deadliest cyclone, having killed 12 people in northern Madagascar and later severely damaging portions of northeastern Mozambique, killing about 240 people and leaving $20 million in damage in the latter country. In February, Cyclone Hollanda struck Mauritius near peak intensity, causing $135 million in damage and two deaths.
The 1994–95 South-West Indian Ocean cyclone season was fairly active, with storms forming regularly from October through April. It was much less damaging than its predecessor, and most of the storms in the season remained over water or only brushed land. The first system was Tropical Depression A1, which formed in October and passed north of Madagascar. The first named storm was Albertine, which formed on November 23 in the northeastern portion of the basin and became one of three intense tropical cyclones. The last storm was Marlene, which was also an intense tropical cyclone and dissipated on April 11.
The 2014–15 South-West Indian Ocean cyclone season was an above average event in tropical cyclone formation. It began on November 15, 2014, and ended on April 30, 2015, with the exception for Mauritius and the Seychelles, for which it ended on May 15, 2015. These dates conventionally delimit the period of each year when most tropical and subtropical cyclones form in the basin, which is west of 90°E and south of the Equator. Tropical and subtropical cyclones in this basin are monitored by the Regional Specialised Meteorological Centre in Réunion.