Recent from talks
Knowledge base stats:
Talk channels stats:
Members stats:
1991–92 Australian region cyclone season
The 1991–92 Australian region cyclone season saw several intense storms. It was also an event in the ongoing cycle of tropical cyclone formation. It ran from 1 November 1991 to 30 April 1992. 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 1991 to 30 June 1992.
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.
On 2 December, a south-southwesterly moving low pressure system formed. Rapidly intensifying, Tropical cyclone Graham was classified the next day about 750 km (470 mi) northwest of Cocos Island. Within 24 hours, an eye developed. Shortly thereafter, Graham turned towards the southeast due to influence of a deep-layer anticyclone to the east. Maximum intensity was reached at 1500 UTC 5 December as a Category 5 system. As the cyclone tracked away from Cocos Island, it encountered less favorable conditions. By 0000 UTC 8 December, the low-level circulation became fully exposed on the northwest side of the deep convection. Graham weakened below cyclone intensity at 1800 UTC 9 December and became devoid of convection the next day.
Tropical cyclone Mark formed within the monsoon trough in the Timor Sea, west of Melville Island, on 6 January. The system tracked rapidly eastwards across northern Australia, entering the Gulf of Carpentaria at 1200 UTC 7 January. Once over water, satellite imagery indicated that the system slowly organized and by 0600 UTC 8 January, whilst approaching the central Gulf of Carpentaria, it was upgraded into a Category 1 cyclone. Upon naming, Mark slowed and adopted a slightly northeastward track in response to enhanced ridging to the south. This track was maintained for the next 40 hours and at 2100 UTC 9 January, Mark crossed the western coast of Cape York Peninsula just south of Weipa. Maximum sustained winds at landfall were estimated at 100 km/h (62 mph) with a central pressure of 980 mbar (29 inHg). Mark soon weakened as it crossed the peninsula and was downgraded to a tropical depression at 1200 UTC 10 January. Mark dissipated later that day. Weipa sustained minor, but widespread damage with failing trees often being a consequence for damage to houses and power lines. High waves brought $3.5 million (AUD) damage to the Weipa port.
A deep depression formed from gale-force westerlies on 5 January. The depression continued to intensify as it drifted slowly west and became a Category 1 cyclone the next day. During the next 12 hours, Betsy rapidly intensified while moving south-southeast slowly. Mean winds associated with the cyclone reached storm-force late on 7 January and the system turned to the southwest and subsequently the cyclone approached the central Vanuatu Islands. By 1800 UTC 8 January, Besty developed hurricane-force winds. Six hours later, the core of the cyclone struck the islands of Ambrym and Malakula in central Vanuatu while developing a large ragged eye. Betsy continued to intensify after existing Vanuatu, and reached maximum intensity very early on 10 January while located 200 km (120 mi) north of New Caledonia. By 11 January, Besty had become less organized. Meanwhile, the eye shrunk and became ragged. was losing organisation, with the large eye (diameter of 165 km) rapidly shrinking and becoming elongated and ragged. Midday 11 January, Betsy recurved sharply to the south and by 13 January Betsy had dissipated. However, the extratropical remnants passed close to the northern coast of New Zealand on 17 January. On Malakula, sustained winds of 118 km/h (73 mph) were recorded between 0400 and 0500 UTC 9 January and the pressure dropped to 959 mbar (28.3 inHg). Tropical cyclone Betsy was blamed for significant damage in Vanuatu and was responsible for the deaths of two people. The worst impact was felt on Efate, where there was a 3 m (9.8 ft) storm surge.
A tropical depression formed in the south Pacific on 11 February. The system steadily developed, and was named Daman on 15 February. Twelve hours later, the cyclone skirted Vanua Lava before passing northwest of Espiritu Santo. After emerging into Coral Sea, Cyclone Daman began curving to the southwest, and then south-southwest. On 17 February, it peaked in intensity as a Category 3 cyclone. The system began weakening shortly thereafter as environmental shear increased, and by Daman was no longer a tropical cyclone. Soon afterwards, the extratropical remnants turned rapidly eastwards, bringing gale-force winds to parts of the North Island of New Zealand. At Manukau Heads, a wind gust of 205 km/h (127 mph) was recorded. Significant tree damage and downed power lines were reported in Auckland.
A low formed on 24 February 550 km (340 mi) east of Cocos Island. The low rapidly intensified under favorable conditions, and at 0600 UTC 25 February, the system was named. Initially, Harriet moved towards the islands, passing just south of North Keeling Island early on 27 February. The storm gradually became better organized, and early on 1 March, Cyclone Harriet attained peak intensity over estimated to have sustained winds of 115 km/h (71 mph) and a central pressure of 930 mbar (27 inHg).
The tropical cyclone weakened somewhat during the following next three days while continuing west. An approaching frontal system from the west resulted in Harriet re-curving to the south on 4 March. The storm continued to weakening due to strong wind shear. Harriet started to accelerate to the southeast on 6 March. The cyclone passed 700 km (430 mi) to the southwest of Cape Leeuwin in southwest Western Australia during the evening of 8 March. Shortly after that, Harriet lost tropical features.
Hub AI
1991–92 Australian region cyclone season AI simulator
(@1991–92 Australian region cyclone season_simulator)
1991–92 Australian region cyclone season
The 1991–92 Australian region cyclone season saw several intense storms. It was also an event in the ongoing cycle of tropical cyclone formation. It ran from 1 November 1991 to 30 April 1992. 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 1991 to 30 June 1992.
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.
On 2 December, a south-southwesterly moving low pressure system formed. Rapidly intensifying, Tropical cyclone Graham was classified the next day about 750 km (470 mi) northwest of Cocos Island. Within 24 hours, an eye developed. Shortly thereafter, Graham turned towards the southeast due to influence of a deep-layer anticyclone to the east. Maximum intensity was reached at 1500 UTC 5 December as a Category 5 system. As the cyclone tracked away from Cocos Island, it encountered less favorable conditions. By 0000 UTC 8 December, the low-level circulation became fully exposed on the northwest side of the deep convection. Graham weakened below cyclone intensity at 1800 UTC 9 December and became devoid of convection the next day.
Tropical cyclone Mark formed within the monsoon trough in the Timor Sea, west of Melville Island, on 6 January. The system tracked rapidly eastwards across northern Australia, entering the Gulf of Carpentaria at 1200 UTC 7 January. Once over water, satellite imagery indicated that the system slowly organized and by 0600 UTC 8 January, whilst approaching the central Gulf of Carpentaria, it was upgraded into a Category 1 cyclone. Upon naming, Mark slowed and adopted a slightly northeastward track in response to enhanced ridging to the south. This track was maintained for the next 40 hours and at 2100 UTC 9 January, Mark crossed the western coast of Cape York Peninsula just south of Weipa. Maximum sustained winds at landfall were estimated at 100 km/h (62 mph) with a central pressure of 980 mbar (29 inHg). Mark soon weakened as it crossed the peninsula and was downgraded to a tropical depression at 1200 UTC 10 January. Mark dissipated later that day. Weipa sustained minor, but widespread damage with failing trees often being a consequence for damage to houses and power lines. High waves brought $3.5 million (AUD) damage to the Weipa port.
A deep depression formed from gale-force westerlies on 5 January. The depression continued to intensify as it drifted slowly west and became a Category 1 cyclone the next day. During the next 12 hours, Betsy rapidly intensified while moving south-southeast slowly. Mean winds associated with the cyclone reached storm-force late on 7 January and the system turned to the southwest and subsequently the cyclone approached the central Vanuatu Islands. By 1800 UTC 8 January, Besty developed hurricane-force winds. Six hours later, the core of the cyclone struck the islands of Ambrym and Malakula in central Vanuatu while developing a large ragged eye. Betsy continued to intensify after existing Vanuatu, and reached maximum intensity very early on 10 January while located 200 km (120 mi) north of New Caledonia. By 11 January, Besty had become less organized. Meanwhile, the eye shrunk and became ragged. was losing organisation, with the large eye (diameter of 165 km) rapidly shrinking and becoming elongated and ragged. Midday 11 January, Betsy recurved sharply to the south and by 13 January Betsy had dissipated. However, the extratropical remnants passed close to the northern coast of New Zealand on 17 January. On Malakula, sustained winds of 118 km/h (73 mph) were recorded between 0400 and 0500 UTC 9 January and the pressure dropped to 959 mbar (28.3 inHg). Tropical cyclone Betsy was blamed for significant damage in Vanuatu and was responsible for the deaths of two people. The worst impact was felt on Efate, where there was a 3 m (9.8 ft) storm surge.
A tropical depression formed in the south Pacific on 11 February. The system steadily developed, and was named Daman on 15 February. Twelve hours later, the cyclone skirted Vanua Lava before passing northwest of Espiritu Santo. After emerging into Coral Sea, Cyclone Daman began curving to the southwest, and then south-southwest. On 17 February, it peaked in intensity as a Category 3 cyclone. The system began weakening shortly thereafter as environmental shear increased, and by Daman was no longer a tropical cyclone. Soon afterwards, the extratropical remnants turned rapidly eastwards, bringing gale-force winds to parts of the North Island of New Zealand. At Manukau Heads, a wind gust of 205 km/h (127 mph) was recorded. Significant tree damage and downed power lines were reported in Auckland.
A low formed on 24 February 550 km (340 mi) east of Cocos Island. The low rapidly intensified under favorable conditions, and at 0600 UTC 25 February, the system was named. Initially, Harriet moved towards the islands, passing just south of North Keeling Island early on 27 February. The storm gradually became better organized, and early on 1 March, Cyclone Harriet attained peak intensity over estimated to have sustained winds of 115 km/h (71 mph) and a central pressure of 930 mbar (27 inHg).
The tropical cyclone weakened somewhat during the following next three days while continuing west. An approaching frontal system from the west resulted in Harriet re-curving to the south on 4 March. The storm continued to weakening due to strong wind shear. Harriet started to accelerate to the southeast on 6 March. The cyclone passed 700 km (430 mi) to the southwest of Cape Leeuwin in southwest Western Australia during the evening of 8 March. Shortly after that, Harriet lost tropical features.