Cyclone Glenda

Last updated

Map key
  Tropical depression (≤38 mph, ≤62 km/h)
  Tropical storm (39–73 mph, 63–118 km/h)
  Category 1 (74–95 mph, 119–153 km/h)
  Category 2 (96–110 mph, 154–177 km/h)
  Category 3 (111–129 mph, 178–208 km/h)
  Category 4 (130–156 mph, 209–251 km/h)
  Category 5 (≥157 mph, ≥252 km/h)
  Unknown
Storm type
Disc Plain black.svg Tropical cyclone
Solid black.svg Subtropical cyclone
ArrowUp.svg Extratropical cyclone, remnant low, tropical disturbance, or monsoon depression

On 15 March, a tropical disturbance developed in the south-western Gulf of Carpentaria. It moved westward, drifting across Top End, and it exited into the Joseph Bonaparte Gulf on 22 March. [1] The Bureau of Meteorology (BoM) office in Darwin, which is the local Tropical Cyclone Warning Centre, began issuing advisories on the system late on 23 March while it was located about 85 km (53 mi) east-south-east of Wyndham, Western Australia. Environmental conditions favored intensification as an anticyclone developed over the storm, which provided good outflow and low vertical wind shear. Initially, the primary inhibiting factor was land interaction. [2] After executing a small loop over water, the disturbance continued westward, crossing over the northern portion of Western Australia before emerging into the Indian Ocean on 26 March. [3] It began tracking west-southwestward just offshore of the Kimberley coastline, and its convection quickly concentrated. At 0000  UTC on 27 March, the Joint Typhoon Warning Center (JTWC) classified it as Tropical Cyclone 20S. Three hours later, the BoM office in Perth upgraded the storm to Tropical Cyclone Glenda about 260 km (160 mi) north of Derby, Western Australia. [2]

Upon reaching open waters, Glenda quickly intensified, and midday on 27 March the BoM upgraded it to tropical cyclone status, or the equivalence of a minimal hurricane. [2] Shortly thereafter, the JTWC followed suit by upgrading it to cyclone status just 12 hours after first warning on the storm. [4] A wind gust of 113 km/h (70 mph) was reported on Adele Island as the cyclone passed nearby. [1] The track turned south westward around a steering ridge over Australia, aided by a mid-latitude trough. By 27 March, Glenda had developed a banding eye, and subsequently began rapid deepening, with warm water temperatures of over 30 °C (86 °F) and a very favourable upper-level environment. [4] At 1200 UTC on 28 March, the JTWC classified Glenda with peak winds of 260 km/h (160 mph) about 235 km (146 mi) west-north-west of Broome, or about 455 km (283 mi) north-north-east of Port Hedland; [4] however, in a subsequent analysis, the JTWC lowered their intensity estimate to 220 km/h (140 mph). [5] At the same time the BoM estimated the cyclone attained peak winds of 205 km/h (125 mph) with gusts to 295 km/h (185 mph), or a Category 5 on the Australian cyclone scale. [3] Its peak intensity of 910  mbar was tied for the fifth most intense tropical cyclone on record in the Australian basin. [6]

Initially, Cyclone Glenda was forecast to intensify further. However, a gradual increase in vertical shear caused the eye to become disorganised, [4] with land interaction contributing to further weakening. The BoM maintained Glenda as a Category 5 cyclone until 29 March, [3] and initially it was forecast to turn southward to move ashore near the populated region of Karratha at high tide. [7] It retained its south west track and passed over several weather stations, one of which recorded sustained winds of 176 km/h (109 mph). [1] Glenda made landfall near the less populated town of Onslow at around 10pm WST (1400 UTC) on 30 March. [8] The cyclone had weakened to a marginal Category 3 at the time of landfall. [8] The JTWC issued its final warning on Glenda shortly after it moved ashore. The cyclone turned south and south-south-eastward and rapidly weakened over land in an area of increasing wind shear, and early on 31 March the BoM downgraded Glenda to a tropical low. [2]

Preparations, impact and aftermath

Severe Tropical Cyclone Glenda
Glenda 28 mar 2006 0200Z.jpg
Glenda prior to peak intensity on 28 March
Most intense Australian cyclones
RankCycloneYearMin. pressure
1 Gwenda 1999 900  hPa (26.58  inHg)
Inigo 2003
3 George 2007 902 hPa (26.64 inHg)
4 Orson 1989 905 hPa (26.72 inHg)
Marcus 2018
6 Theodore 1994 910 hPa (26.87 inHg)
Vance 1999
Fay 2004
Glenda 2006
Source: Australian Bureau of Meteorology [9]
Cyclone Glenda near landfall on 30 March STC Glenda 30 mar 2006 0610Z.jpg
Cyclone Glenda near landfall on 30 March

The precursor system dropped heavy rainfall on 23 March in the eastern Kimberley in the state of Western Australia. The rainfall led to record flooding in the area; the flooding washed out several roads near Kununurra, including a portion of the Great Northern Highway. Six people were evacuated due to the flooding. [10]

Offshore, the threat of Glenda prompted officials to close oil, representing a lack of production of 154,000 barrels of oil. Additionally, natural gas fields were closed, and several ports along the coastline were shut down during the passage of the storm. [11] Prior to the storm's landfall, officials issued a Red Alert for several communities. Storm shelters were opened in Karratha and Onslow, [10] while a few hundred people evacuated along the coastline. [12]

Glenda made landfall near Onslow, where sustained winds reached 117 km/h (73 mph). There, the storm produced a 24‑hour rainfall total of 206 mm (8.1 in), which is the sixth greatest daily precipitation on record in the town. Several other locations reported over 200 mm (7.9 in), though overall precipitation was less than a usual landfalling tropical cyclone. [1] The rainfall flooded several roads. [10] The winds downed several trees and power lines, [13] which left about 2,000 people in Karratha without electricity; [12] the power outage was quickly repaired. [13] Several windows at the hospital in Onslow were broken, resulting in some minor water damage. [13] Overall damage was minor, [3] and no deaths or injuries were reported, [13] which was credited to the storm's weakening and preparations in the landfall area. [3] In all, damages from the storm amounted to A$1.2 million (US$965,000). [14] The disruption to shipping companies resulted in economic losses of A$30 million (US$24.1 million). [15] Oil companies reported a loss of 500 tonnes during the economic quarter due to the cyclone. [16] The Onslow Salt company reported upwards of A$20 million (US$16 million) in lost revenue. [14]

Following the storm, residents and companies affected by the storm were allowed to file insurance claims. About A$240,000 (US$193,000) was filed in repair claims for council buildings and A$69,000 (US$55,000) in airport insurance. About A$99,000 (US$79,000) and A$300,000 (US$241,000) was provided in financial support for television and broadcasting infrastructure and aerodrome infrastructure respectively. [14]

The Bureau of Meteorology retired the name Glenda following its usage. [17]

See also

Related Research Articles

<span class="mw-page-title-main">Cyclone Vance</span> Category 5 Australian region cyclone in 1999

Severe Tropical Cyclone Vance was a tropical cyclone that struck Western Australia during the active 1998–99 Australian region cyclone season, and was also one of six tropical cyclones to form off the coast of Australia during that season. When making landfall the Learmonth Meteorological Office recorded the highest Australian wind gust of 267 km/h (166 mph). The previous highest gust was 259 km/h (161 mph) at nearby Mardie during Cyclone Trixie. This record was surpassed in 2010 after a world record wind-gust of 408 km/h (254 mph) at Barrow Island during Cyclone Olivia in 1996 was declared official by the World Meteorological Organisation.

<span class="mw-page-title-main">1999–2000 Australian region cyclone season</span>

The 1999–2000 Australian region cyclone season was a slightly above average tropical cyclone season. It ran from 1 November 1999 to 30 April 2000. The regional tropical cyclone operational plan also defines a "tropical cyclone year" separately from a "tropical cyclone season", with the "tropical cyclone year" for this season lasting from 1 July 1999 to 30 June 2000.

<span class="mw-page-title-main">2005–06 Australian region cyclone season</span> Tropical cyclone season

The 2005–06 Australian region cyclone season was an above average tropical cyclone season. It began on 1 November 2005 and ended on 30 April 2006. The regional tropical cyclone operational plan also defines a tropical cyclone year separately from a tropical cyclone season, which runs from 1 July 2005 to 30 June 2006.

<span class="mw-page-title-main">2003–04 South-West Indian Ocean cyclone season</span> Cyclone season in the Southwest Indian Ocean

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.

<span class="mw-page-title-main">2002–03 Australian region cyclone season</span> Cyclone season in the Australian region

The 2002–03 Australian region cyclone season included Cyclone Inigo, which tied with Cyclone Gwenda in 1999 as the most intense tropical cyclone on record in the Australian basin. It began on 1 November 2002 and ended on 30 April 2003. The regional tropical cyclone operational plan also defines a tropical cyclone year separately from a tropical cyclone season, which runs from 1 July 2002 to 30 June 2003. These dates conventionally delimit the period of each year when most tropical cyclones form in the Australian region, which is defined as in the southern hemisphere between 90°E and 180°E. The season's ten tropical depressions existed within these dates, with the first, designated as Tropical Cyclone 07S, entering the basin on 27 December 2002. The last system, Cyclone Epi, dissipated on 6 June 2003. Tropical cyclones in this area were monitored by four Tropical Cyclone Warning Centres (TCWCs): the Australian Bureau of Meteorology (BOM) in Perth, Darwin, and Brisbane and one in Port Moresby, Papua New Guinea.

<span class="mw-page-title-main">Cyclone Inigo</span> Category 5 Australian region cyclone in 2003

Severe Tropical Cyclone Inigo is tied with Cyclone Gwenda for being the most intense recorded cyclone in the Australian region in terms of pressure, with the possible exception of Cyclone Mahina. Inigo developed from a tropical low that crossed eastern Indonesia in late March 2003. Becoming a named tropical cyclone on 1 April, Inigo rapidly intensified as it tracked southwestward, reaching a minimum central pressure of 900 hPa on 4 April with maximum 1 minute sustained winds of 170 mph. An approaching trough weakened the cyclone and turned it to the southeast, and on 8 April, Inigo dissipated after making landfall on Western Australia, as a minimal tropical storm.

<span class="mw-page-title-main">2008–09 Australian region cyclone season</span> Tropical cyclone season

The 2008–09 Australian region cyclone season was a near average tropical cyclone season. It officially started on 1 November 2008, and officially ended on 30 April 2009. This season was also the first time that the BoM implemented a "tropical cyclone year." The regional tropical cyclone operational plan defines a "tropical cyclone year" separately from a "tropical cyclone season"; the "tropical cyclone year" began on 1 July 2008 and ended on 30 June 2009.

<span class="mw-page-title-main">1994 North Indian Ocean cyclone season</span>

The 1994 North Indian Ocean cyclone season was a below-average year in which eight tropical cyclones affected seven countries bordering the North Indian Ocean. The India Meteorological Department tracks all tropical cyclones in the basin, north of the equator. The first system developed on March 21 in the Bay of Bengal, the first March storm in the basin since 1938. The second storm was the most powerful cyclone of the season, attaining maximum sustained winds of 215 km/h (135 mph) in the northern Bay of Bengal. Making landfall near the border of Bangladesh and Myanmar, the cyclone killed 350 people and left US$125 million in damage.

<span class="mw-page-title-main">1998–99 Australian region cyclone season</span>

The 1998–99 Australian region cyclone season was an above average tropical cyclone season that featured Gwenda, the most intense tropical cyclone in the Australian Region. It began on 1 November 1998 and ended on 30 April 1999. The regional tropical cyclone operational plan also defines a tropical cyclone year separately from a tropical cyclone season, which runs from 1 July 1998 to 30 June 1999.

<span class="mw-page-title-main">Cyclone Graham</span> Category 1 Australian region cyclone in 2003

Cyclone Graham of the 2002–03 Australian region cyclone season was a weak tropical storm that affected Australia during late February and early March 2003. Graham originated from an area of convection that emerged onto water after sitting over Australia on 23 February. The interaction with a monsoon trough formed an area of low pressure that developed into Tropical Cyclone Graham on 27 February. The storm moved slowly to the east-southeast, and after turning to the south it peaked as a tropical storm and made landfall on Western Australia the next day. The cyclone weakened as it moved inland, and dissipated on 1 March. The storm dropped heavy rainfall and caused high winds, which produced flooding and downed trees. One fatality occurred, though no significant damages were reported.

<span class="mw-page-title-main">1984–85 Australian region cyclone season</span>

The 1984–85 Australian region cyclone season was one of the most active seasons on record. It officially started on 1 November 1984, and officially ended on 30 April 1985.

<span class="mw-page-title-main">1988–89 Australian region cyclone season</span>

The 1988–89 Australian region cyclone season was a slightly above average tropical cyclone season. It officially started on 1 November 1988, and officially ended on 30 April 1989. The regional tropical cyclone operational plan defines a "tropical cyclone year" separately from a "tropical cyclone season"; the "tropical cyclone year" began on 1 July 1988 and ended on 30 June 1989.

<span class="mw-page-title-main">Cyclone Emma (2006)</span> Category 1 Australian region cyclone in 2006

Tropical Cyclone Emma was a weak but unusually large tropical cyclone that affected a substantial portion of Western Australia during the 2005–06 Australian region cyclone season. Forming out of an area of low pressure on 25 February, the precursor to Emma slowly tracked southward. Although classified tropical, the structure of the system represented that of a monsoonal storm. However, low wind shear and well-developed outflow gradually allowed convection to develop near the centre of circulation. As the system approached the Pilbara coastline of Western Australia on 27 February, it intensified into a Category 1 cyclone and attained peak 10-minute sustained winds of 75 km/h (47 mph). After moving inland near Mardie, Emma weakened to a tropical low but became exceedingly large; its cloud cover obscured most of Western Australia. The remnants of the weak storm persisted until 1 March, at which time they dissipated over the Great Australian Bight.

<span class="mw-page-title-main">Cyclone Gwenda</span> Category 5 Australian region cyclone in 1999

Severe Tropical Cyclone Gwenda is tied with Cyclone Inigo as the most intense Australian tropical cyclone on record, with a barometric pressure of 900 hPa (mbar) and was the most intense storm worldwide in 1999. Forming out of a tropical disturbance over the Arafura Sea on 2 April 1999, the precursor to Gwenda tracked slowly westward and gradually became more organised. On 4 April, the system developed into a Category 1 cyclone and was named Gwenda. It began to undergo explosive intensification the following day, and in a 30-hour span ending early on 7 April, the storm's maximum 10-minute sustained wind speed increased from 75 to 225 km/h and its barometric pressure decreased to 900 hPa (mbar). The Joint Typhoon Warning Center reported that the storm had peaked as a high-end Category 4 equivalent on the Saffir–Simpson hurricane scale.

<span class="mw-page-title-main">Cyclone Clare</span> Category 3 Australian region cyclone in 2006

Severe Tropical Cyclone Clare was a moderately strong cyclone that struck Western Australia in January 2006. The storm formed as an area of low pressure in the Arafura Sea, and moved westward. After receiving the name Clare on 7 January, the system ultimately peaked at Category 3 intensity on the Australian tropical cyclone scale. It moved ashore on the coast of the Pilbara and proceeded inland, dissipating on 10 January. Clare produced winds of 142 km/h (88 mph) at Karratha and triggered widespread torrential rainfall that led to flooding. Following its usage, the name Clare was retired by the Bureau of Meteorology, and will never be used again for a tropical cyclone in the area.

<span class="mw-page-title-main">2016–17 Australian region cyclone season</span> Tropical cyclone season

The 2016–17 Australian region cyclone season, despite a very high number of tropical lows, was a slightly below-average season in terms of activity, with nine tropical cyclones, three of which intensified further into severe tropical cyclones; though it was much more active than the previous season. The season was the first to have a severe tropical cyclone since the 2014–15 season. It was the period of the year when most tropical cyclones form in the Southern Indian Ocean and Pacific Oceans between 90°E and 160°E. The season officially ran from 1 November 2016 to 30 April 2017, however, a tropical cyclone could form at any time between 1 July 2016 and 30 June 2017 and would count towards the season total. The first named storm, Yvette, developed during 21 December, and the final named storm, Greg, left the region on 3 May as a remnant low. This season was also the second-costliest tropical cyclone season on record in the Australian region basin, behind only the 2010–11 season, with a total of AUD$3.7 billion in damages incurred by the various storms, mostly from Cyclone Debbie.

<span class="mw-page-title-main">Cyclone John</span> Category 5 Australian region cyclone in 1999

Severe Tropical Cyclone John was an intense tropical cyclone that rapidly deepened offshore before devastating areas of Western Australia. The system was the second cyclone and first severe tropical cyclone of the active 1999–00 Australian region cyclone season. Cyclone John developed from a monsoon trough positioned northwest of Australia on 9 December 1999. As it moved to the west and later south as the result of a subtropical ridge under favourable conditions, the cyclone was able to rapidly intensify. John reached peak intensity on 14 December as a Category 5 cyclone on the Australian cyclone scale, the highest rating possible. Cyclone John later began interacting with a mid–latitude trough, which slightly weakened the cyclone prior to making landfall near Whim Creek early on 15 December. Increasingly unfavourable conditions further inland resulted in the cyclone's rapid weakening, before it dissipated during the next day.

<span class="mw-page-title-main">Cyclone Sam</span> Category 5 Australian region cyclone in 2000

Severe Tropical Cyclone Sam was an intense tropical cyclone that brought flooding rainfall to a wide swath of northern Australia in December 2000. The first tropical cyclone of the regional season, Sam originated from a tropical low that formed in the Arafura Sea on 28 November. Tracking generally westward, the initial low-pressure area remained generally weak until it entered the Timor Sea, by which time it had strengthened into a tropical cyclone on 5 December. Though a subtropical ridge was forcing the cyclone westward at the time, an approaching shortwave trough caused Sam to track southward the following day, towards the Australian coast. During its southward progression, Sam rapidly intensified, and reached its peak intensity on 8 December. Soon afterwards, the storm made landfall near Lagrange, Western Australia at the same intensity. Once inland, Sam was slow to weaken as it re-curved eastward, and persisted for nearly a week inland before dissipating on 14 December.

<span class="mw-page-title-main">Cyclone Bobby</span> Category 4 Australian region tropical cyclone in 1995

Severe Tropical Cyclone Bobby set numerous monthly rainfall records in parts of the Goldfields-Esperance regions of Western Australia, dropping up to 400 mm (16 in) of rain in February 1995. The fourth named storm of the 1994–95 Australian region cyclone season, Bobby developed as a tropical low embedded within a monsoon trough situated north of the Northern Territory coastline on 19 February. The storm gradually drifted southwestward and later southward under low wind shear, strengthening enough to be assigned the name Bobby by the Australian Bureau of Meteorology (BoM). The storm rapidly deepened as it approached the coast of Western Australia, and attained its peak intensity of 925 mbar at 0900 UTC on 24 February with 10-minute maximum sustained winds of 195 km/h (120 mph). After making landfall as a somewhat weaker cyclone near Onslow, the remnants of Bobby drifted southeastward, gradually weakening, before dissipating over the southern reaches of Western Australia.

<span class="mw-page-title-main">Cyclone Damien</span> Category 2 Cyclone in 2020

Severe Tropical Cyclone Damien was the strongest cyclone to make landfall on the Western Australian coast since Cyclone Christine in 2013 and the second-strongest cyclone in the 2019–20 Australian region cyclone season after Cyclone Ferdinand. The fifth tropical low, and the third named storm of the 2019–20 Australian region cyclone season, Damien originated from a monsoon trough over Kimberley.

References

  1. 1 2 3 4 "Significant Weather — March 2006" (PDF). Bureau of Meteorology. 2006. Retrieved 13 April 2008.
  2. 1 2 3 4 Gary Padgett (2006). "March 2006 Worldwide Tropical Cyclone Summary". Australia Severa Weather. Retrieved 13 April 2008.
  3. 1 2 3 4 5 Perth Tropical Cyclone Warning Centre (2006). "Severe Tropical Cyclone Glenda" (PDF). Bureau of Meteorology. Retrieved 26 October 2024.
  4. 1 2 3 4 Joint Typhoon Warning Center (2006). "Warnings on Cyclone Glenda". Australia Severe Weather. Retrieved 13 April 2008.
  5. Joint Typhoon Warning Center (2007). "Best Track for Cyclone Glenda". United States Navy. Archived from the original on 7 June 2011. Retrieved 26 September 2008.
  6. "Australian Region Best Track 1907-2006" (Zip). Bureau of Meteorology. 2006. Retrieved 4 November 2007.[ permanent dead link ]
  7. "WA Tropical Cyclone Season Summary 2005-06". Bureau of Meteorology. 2006. Retrieved 14 April 2008.
  8. 1 2 "Severe Tropical Cyclone Glenda" (PDF). Perth Tropical Cyclone Warning Centre. Bureau of Meteorology. Retrieved 6 January 2013.
  9. "Australian Tropical Cyclone Database" (CSV). Australian Bureau of Meteorology. 30 June 2023. Retrieved 30 June 2023. A guide on how to read the database is available here.
  10. 1 2 3 Fire and Emergency Services Authority (2007). "2005-06 Cyclones in Western Australia" (PDF). Archived from the original (PDF) on 20 July 2008. Retrieved 15 April 2008.
  11. Bloomberg (29 March 2006). "Cyclone Glenda Shuts Ports, Oil Fields in Australia". Bloomberg News . Retrieved 15 April 2008.
  12. 1 2 Impact Forecasting (2006). "Annual Global Climate and Catastrophe Report: 2006" (PDF). Retrieved 15 April 2008.[ permanent dead link ]
  13. 1 2 3 4 Australian Associated Press (31 March 2006). "Pilbara unscathed by cyclone Glenda". The Age. Melbourne. Retrieved 15 April 2008.
  14. 1 2 3 Shire of Ashburton (19 June 2007). "Ordinary Council Meeting". Archived from the original on 25 July 2008. Retrieved 10 June 2009.
  15. Staff Writer (30 March 2006). "Cyclone Glenda makes landfall". ABC News. Retrieved 10 June 2009.
  16. Staff Writer (26 April 2006). "Activities Report for the Period Ended 31 March 2006" (PDF). Minara Resources Limited. Retrieved 10 June 2009.
  17. RA V Tropical Cyclone Committee (2024). Tropical Cyclone Operational Plan for the South-East Indian Ocean and the Southern Pacific Ocean 2024 (PDF) (Report). World Meteorological Organization. Retrieved 14 October 2024.