1989–90 Australian region cyclone season

(Redirected from Cyclone Greg (1990))

The 1989–90 Australian region cyclone season was an above average tropical cyclone season. It was also an event in the ongoing cycle of tropical cyclone formation. It ran from 1 November 1989 to 30 April 1990. The regional tropical cyclone operational plan also defines a tropical cyclone year separately from a tropical cyclone season, and the "tropical cyclone year" ran from 1 July 1989 to 30 June 1990.

1989–90 Australian region cyclone season
Season summary map
Seasonal boundaries
First system formedJuly 14, 1989
Last system dissipatedApril 18, 1990
Strongest storm
NameAlex
 • Maximum winds220 km/h (140 mph)
(10-minute sustained)
 • Lowest pressure927 hPa (mbar)
Seasonal statistics
Tropical lows14
Tropical cyclones14
Severe tropical cyclones5
Total fatalitiesUnknown
Total damageUnknown
Related articles
Australian region tropical cyclone seasons
1987–88, 1988–89, 1989–90, 1990–91, 1991–92

Tropical cyclones in this area were monitored by four Tropical Cyclone Warning Centres (TCWCs): the Australian Bureau of Meteorology in Perth, Darwin, and Brisbane; and TCWC Port Moresby in Papua New Guinea.

Seasonal summary

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Tropical cyclone scales#Comparisons across basins

Systems

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Tropical Storm 02S

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Tropical storm (SSHWS)
DurationJuly 14 – July 16
Peak intensity65 km/h (40 mph) (1-min);
997 hPa (mbar)

Tropical Storm 02S existed from July 14 to July 16.

Tropical Cyclone Pedro

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Category 2 tropical cyclone (Australian scale)
Category 1 tropical cyclone (SSHWS)
DurationNovember 4 – November 13
Peak intensity110 km/h (70 mph) (10-min);
982 hPa (mbar)

At 0:00 UTC on November 6, the BOM detected an area of low pressure within a monsoonal trough near 7.8°S, 97.2°E., which gradually organized while drifting westward for the next couple of days. On November 8, the disturbance strengthened into a tropical cyclone and was named Pedro. The cyclone continued to intensify before reaching its peak intensity at 13:00 UTC on November 10 with 10-minute sustained winds of around 70 mph (110 km/h) and a minimum pressure of 982 mbar (29.0 inHg), with a short-lived eye visible on satellite imagery. As Pedro moved southward, strong vertical wind shear left the low-level center bare and displaced convection to the northwestern side of the storm. At 0:00 UTC on November 13, Pedro's winds weakened below gale-force and the system degenerated into a remnant system, which dissipated the following day.[1]

Pedro passed within 85 miles (137 km)[nb 1] of Cocos Island, where a peak wind gust of around 85 mph (137 km/h) was recorded. At least 7.9 inches (200 mm) of precipitation fell on the island within a 24-hour period, causing localized flooding. A palm plantation and loading wharf were damaged by the storm.[1]

Severe Tropical Cyclone Felicity

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Category 3 severe tropical cyclone (Australian scale)
Category 1 tropical cyclone (SSHWS)
Duration13 December – 20 December
Peak intensity140 km/h (85 mph) (10-min);
975 hPa (mbar)

On 13 December, the BoM started to monitor a monsoon low, that had developed within the Arafura Sea to the northeast of Darwin.[2] Over the next day, the system moved southeastwards over the Northern Territory, before it re-curved slightly and entered the Gulf of Carpentaria.[2] Early on 15 December, the system was named Felicity by TCWC Brisbane, after it had become a category 1 tropical cyclone on the Australian Scale.[2] During that day the JTWC initiated advisories on the system and designated it as Tropical Cyclone 07P, with peak 1-minute sustained wind speeds of 110 km/h (68 mph).[3] TCWC Brisbane subsequently reported peak 10-minute sustained wind speeds of 110 km/h (68 mph), before the system made landfall over the Cape York Peninsula where it weakened below cyclone intensity.[2] The system subsequently moved into the Coral Sea during 16 December, where it started to rapidly deepen, but did not reattain the classical characteristics of a tropical cyclone.[2][4] As a result, both TCWC Nadi and TCWC Brisbane treated the system as a tropical depression over the next four days despite winds of between 110 and 115 km/h (68 and 71 mph) being observed in the southwest quadrant.[2][4] Felicity subsequently dissipated during 20 December as it was absorbed by a short-wave trough of low pressure to the north of New Zealand.[2][4] Some minor damage to vegetation was recorded on the Cape York Peninsula.[2][4]

Tropical Cyclone Rosita

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Category 1 tropical cyclone (Australian scale)
Tropical storm (SSHWS)
DurationJanuary 4 – January 17
Peak intensity85 km/h (50 mph) (10-min);
988 hPa (mbar)

Rosita was first noted as a low-pressure system at 18:00 UTC on January 4 while it located well south of Java. Moving swiftly westward, the disturbance gradually organized for two days until slightly weakening due to increasing vertical wind shear. The system remained quasi-stationary until January 9 when a developing ridge in the middle-latitudes forced the disturbance northwestward. The low was ill-defined with a weak and sheared structure on satellite imagery while moving equatorward. By 6:00 UTC the following day, convection began to redevelop and consolidate through January 12 as the disturbance strengthened.[5]

At 15:00 UTC on January 13, tropical storm-force winds formed around the center, prompting the BOM to upgrade the low into Tropical Cyclone Rosita. The nascent cyclone tracked south-southeastward, remaining under the influence of vertical wind shear causing majority of convection to be displaced west of the center. Rosita once again changed course late the next day, shifting northwestward as it lost gale-force winds. The remnants tracked around the periphery of the more intense Severe Tropical Cyclone Sam, before moving equatorward and dissipating on January 17.[5]

Severe Tropical Cyclone Sam

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Category 3 severe tropical cyclone (Australian scale)
Category 1 tropical cyclone (SSHWS)
DurationJanuary 11 – January 21
Peak intensity130 km/h (80 mph) (10-min);
966 hPa (mbar)

Sam, 11 to 21 January 1990, near Western Australia

Tropical Cyclone Tina

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Category 2 tropical cyclone (Australian scale)
Category 1 tropical cyclone (SSHWS)
DurationJanuary 24 – January 29
Peak intensity95 km/h (60 mph) (10-min);
972 hPa (mbar)

Tina, 24 to 29 January 1990, crossed Western Australia

Tropical Cyclone Nancy

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Category 2 tropical cyclone (Australian scale)
Category 1 tropical cyclone (SSHWS)
DurationJanuary 26 – February 4
Peak intensity110 km/h (70 mph) (10-min);
980 hPa (mbar)

In late January, a monsoon trough spawned a tropical depression on 26 January, over the Coral Sea. The depression developed good outflow, before gaining tropical cyclone characteristic on 31 January, and was designated as Tropical Cyclone Nancy. An upper-level trough forced the storm southward, before shifting southwestward. At 3:00 UTC on 1 February, Nancy reached its peak intensity with 10-minute sustained winds of around 60 mph (97 km/h) and a minimum pressure of 975 mbar. Between 1–2 February, the cyclone gradually moved just offshore the Brisbane area. Nancy then weakened while continuing to move southward, before transitioning into an extratropical low on 4 February. The remnants eventually dissipated to the west of New Zealand on 8 February.[6]

Nancy caused flash floods responsible for five fatalities.[7]

Severe Tropical Cyclone Vincent

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Category 3 severe tropical cyclone (Australian scale)
Category 1 tropical cyclone (SSHWS)
DurationFebruary 25 – March 6
Peak intensity130 km/h (80 mph) (10-min);
965 hPa (mbar)

Vincent, 25 February to 6 March 1990, near Western Australia

Tropical Cyclone Greg

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Category 1 tropical cyclone (Australian scale)
Tropical depression (SSHWS)
DurationFebruary 28 – March 5
Peak intensity75 km/h (45 mph) (10-min);
990 hPa (mbar)

Greg, 28 February to 5 March 1990, Gulf of Carpentaria

Tropical Cyclone Walter–Gregoara

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Category 2 tropical cyclone (Australian scale)
Tropical storm (SSHWS)
DurationMarch 4 – March 13 (Exited basin)
Peak intensity95 km/h (60 mph) (10-min);
985 hPa (mbar)

Walter existed from 3 to 27 March 1990.

Tropical Cyclone Hilda

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Category 2 tropical cyclone (Australian scale)
Tropical storm (SSHWS)
DurationMarch 4 – March 7
Peak intensity110 km/h (70 mph) (10-min);
970 hPa (mbar)

Cyclone Hilda had cloud tops estimated at 19,200 metres (63,000 ft) tall. The measured cloud top temperature was −100 °C (−148 °F) which is the coldest cloud-top temperature ever measured.[8][9] This record lasted until Typhoon Kammuri in 2019 with cloud tops of −109.35 °C (−164.83 °F).[10]

Severe Tropical Cyclone Alex

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Category 5 severe tropical cyclone (Australian scale)
Category 4 tropical cyclone (SSHWS)
DurationMarch 14 – March 26
Peak intensity220 km/h (140 mph) (10-min);
927 hPa (mbar)

Alex was a fairly intense system. It existed from 14 to 26 March 1990. Despite the intensity, Alex never caused significant damage.

Severe Tropical Cyclone Ivor

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Category 4 severe tropical cyclone (Australian scale)
Category 1 tropical cyclone (SSHWS)
DurationMarch 14 – March 26
Peak intensity165 km/h (105 mph) (10-min);
965 hPa (mbar)

Ivor, 14 to 26 March 1990, crossed Cape York, Queensland

Tropical Cyclone Bessi

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Category 1 tropical cyclone (Australian scale)
Tropical storm (SSHWS)
DurationApril 11 – April 18
Peak intensity75 km/h (45 mph) (10-min);
990 hPa (mbar)

Bessi, 11 to 18 April 1990, Indian Ocean

Season effects

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Name Dates Peak intensity Areas affected Damage
(USD)
Deaths Refs
Category Wind speed Pressure
Rosita 4 – 17 January 1990 Category 1 tropical cyclone 85 km/h (50 mph) 988 hPa (29.18 inHg) None None None [11]
Tina 25 – 28 January 1990 Category 2 tropical cyclone 95 km/h (60 mph) 976 hPa (28.82 inHg) Western Australia Minor None [12]
Nancy 28 January – 4 February 1990 Category 2 tropical cyclone 110 km/h (70 mph) 976 hPa (28.82 inHg) Queensland, New South Wales, New Zealand Unknown Unknown [13]
Greg 28 February – 5 March 1990 Category 1 tropical cyclone 75 km/h (45 mph) 990 hPa (29.23 inHg) None None None [14][15]
Walter –
Gregoara
3 – 13 March 1990 Category 2 tropical cyclone 95 km/h (60 mph) 985 hPa (29.09 inHg) None None None [16]
Hilda 4 – 13 March 1990 Category 2 tropical cyclone 110 km/h (70 mph) 970 hPa (28.64 inHg) New Caledonia Unknown Unknown [17]
Bessi 15 – 18 April 1990 Category 1 tropical cyclone 85 km/h (50 mph) 990 hPa (29.23 inHg) None None None [18]

See also

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Notes

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  1. ^ This calculation is rounded to the nearest tenth, which is why it may differ from others.

References

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  1. ^ a b "Tropical Cyclone Pedro". Bureau of Meteorology. Retrieved May 9, 2021.
  2. ^ a b c d e f g h Tropical Cyclone Felicity (Report). Australian Bureau of Meteorology. Archived from the original on 10 April 2012. Retrieved 26 May 2014.
  3. ^ Joint Typhoon Warning Center; Naval Pacific Meteorology and Oceanography Center. Annual Tropical Cyclone Report: 1990 (PDF) (Report). United States Navy, United States Air Force. p. 234. Archived from the original (PDF) on 19 October 2016. Retrieved 26 May 2014.
  4. ^ a b c d Singh, Arveen K; Fiji Meteorological Service (Summer 1990). DeAngellis, Richard M (ed.). "Tropical depression in Coral Sea (former T.C. Felicity), December 18–20, 1989" (Mariners Weather Log). 34 (3). United States National Oceanic and Atmospheric Administration's National Oceanographic Data Service: 48. hdl:2027/uiug.30112104094245. {{cite journal}}: Cite journal requires |journal= (help)
  5. ^ a b "Tropical Cyclone Rosita" (PDF). Bureau of Meteorology. Retrieved May 9, 2021.
  6. ^ "Tropical Cyclone Nancy". Bureau of Meteorology. Retrieved January 22, 2021.
  7. ^ "EMA Disasters Database". Archived from the original on 2011-09-27.
  8. ^ Jiang, Haiyan; Tao, Cheng (2014-06-01). "Contribution of Tropical Cyclones to Global Very Deep Convection". Journal of Climate. 27 (11): 4313–4336. doi:10.1175/JCLI-D-13-00085.1. ISSN 0894-8755.
  9. ^ Ebert, Elizabeth E.; Holland, Greg J. (1992-10-01). "Observations of Record Cold Cloud-Top Temperatures in Tropical Cyclone Hilda (1990)". Monthly Weather Review. 120 (10): 2240–2251. doi:10.1175/1520-0493(1992)120<2240:OORCCT>2.0.CO;2. ISSN 1520-0493.
  10. ^ Bachmeier, Scott (30 November 2019). "Typhoon Kammuri in the West Pacific Ocean, with record cold cloud-top temperatures". Cooperative Institute for Meteorological Satellite Studies. Retrieved 21 May 2023.
  11. ^ 1990 Tropical Cyclone Rosita (1990005S13112) (Report). International Best Track Archive for Climate Stewardship. Retrieved 28 May 2022.
  12. ^ Ready, Steve; Woodcock, Frank (2 June 1992). "The South Pacific and Southeast Indian Ocean tropical cyclone season 1989–90" (PDF). Australian Meteorological Magazine. 40: 111–121. Retrieved 25 December 2014.
  13. ^ "1990 Severe Tropical Cyclone Nancy (1990027S18156)". International Best Track Archive for Climate Stewardship. Retrieved 28 May 2022.
  14. ^ Tropical Cyclone Greg (Report). Australian Bureau of Meteorology. Retrieved 27 May 2022.
  15. ^ "1990 Tropical Cyclone Greg (1990059S13135)". International Best Track Archive for Climate Stewardship. Retrieved 28 May 2022.
  16. ^ "1990 Intense Tropical Cyclone Gregoara:Walter (1990062S13091)". International Best Track Archive for Climate Stewardship. Retrieved 28 May 2022.
  17. ^ "1990 Tropical Cyclone Hilda (1990060S15170)". International Best Track Archive for Climate Stewardship. Retrieved 28 May 2022.
  18. ^ Tropical Cyclone Bessi (PDF) (Report). Australian Bureau of Meteorology. Retrieved 27 May 2022.