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On the 14th of March 1999, two groups of thunderstorms had coelesced within the monsoon trough that lay across northern Australia, one in the Gulf of Carpentaria, the other in the Indian Ocean near the Indonesian island of Sumba.
No one knew at the time that these two storm seeds, one to be given a male name, the other a female name, were destined to become twin severe tropical cyclones, the male to become the most intense cyclone to hit mainland Australia in recorded history.
Throughout the day, and the night, the male storm seed drifted slowly westwards in the monsoon trough across Arnhem Land, whilst the female storm seed drifted slowly SW in the Indian Ocean.
During the day on 16th, the male storm embryo meandered lazily in the womb of the Van Deimen Gulf, a body of shallow warm water that is a perfect environment for a tropical storm to brew over. His sister, who was now a developing Tropical Depression, was still drifting slowly SW out in the Indian Ocean.
After nightfall, the budding male storm drifted slowly WSW, coming to rest for the night over Darwin, the Northern Territory's Capital City, as if in preparation for the long journey that lay ahead.
On the morning of the 17th, he began to drift slowly WNW out across Beagle Gulf, another large body of shallow water, and in the late morning, when south of Bathurst Island, began to move at a leisurely 5 knots (10 km/hr) WSW out towards the Timor Sea and his sister in the Indian Ocean, who by this time had quickly developed into a Tropical Cyclone Category 2 going by the name of 'Elaine'.
During the heat of the afternoon, he began to slowly gather strength, and during the evening developed Gales of 90 km/hr, and after midnight, slowly increased speed and took on a more westerly course, whilst his fast developing sister Elaine had become a full blown Category 3 severe cyclone.
On the morning of the 18th, he moved out into 'cyclone alley', a rather apt local name for the stretch of warm water between the NW Australian mainland and the islands of Indonesia, that is noted as being a pathway for the passage of some of the most severe tropical cyclones on Earth.
When the warm and moist NW winds flow across the Equator from Asia and form a monsoon trough across northern Australia, and the SE trades blow across continental Australia picking up considerable heat from the vast inland deserts basking in the tropical summer sunshine, conditions are right for severe cyclones to form, and, as they travel down the NW Australian coast, they often become very severe storms by the time they move down towards the very hot NW corner of the continent.
Anyway, the brewing storm continued to gather speed and intensity, generating winds up to 100 km/hr and travelling westwards at 18 km/hr across the Timor Sea to the North of the Joseph Bonapart Gulf and the meat industry town of Wyndham, whilst Elaine had blown up to full intensity, with sustained winds of 75 knots (140 km/hr) near the centre.
In the heat of the afternoon, he was truly born when he became a Category 1 cyclone, and was given the name 'Vance'.
Now he had an identity, and, as if in youthful exuberation, he raced along at a strapping pace of 25 km/hr with wind gusts of 120 km/hr, passing to the North of the Kimberley coast, wheras Elaine, now moving in a more southerly course, being drawn that way by a trough that had developed to the east of a stationary High in the south-eastern Indian Ocean, was losing contact with the monsoon flow.
He continued growing in the evening, having become a mature Category 2 cyclone with wind gusts of 125 km/hr, and continued gaining strength throughout the night.
By the morning of the 19th, his pace had slowed a little to 22km/hr, and he had taken on a new course, now travelling WSW, towards his sister, Elaine, who, having passed her prime now that she was detached from the monsoon flow, had decayed rapidly to a Category 2 cyclone as she fled southwards at about 20 km/hr.
By mid-morning, with the monsoon flow all to himself, his wind gusts had increased to 150 km/hr as he passed to within 485 km to the NNW of the pearling town of Broome, and he continued growing throughout the day as he passed to the N of the iron ore port of Port Hedland.
During the evening, being fed by the flow of hot air from continental Australia, he had strengthened to become a Severe Category 3 cyclone, a real force to be reckoned with, and by midnight he was packing wind gusts of 190 km/hr, already surpassing the maximum strength of Elaine, who had now weakened to a Category 1 .
On the morning of the 20th, he was 570 km N of Karratha and 715 km NNW of Onslow at 9am, and had become a very destructive Category 4 cyclone, with wind gusts to 240 km/hr, having swung more to the SW and slowed to 20 km/hr, still being drawn towards Elaine, who by now was a rain depression travelling SE at about 26 km/hr, preparing to cross the coast near Kalbarri, about 500 km NNW of the West Australian Capital, Perth.
As the day wore on he slowed further, no longer being drawn towards Elaine, who had crossed the coast, and, determined to make her mark in history before degenerating completely, dumped record rainfall across part of WA, that flooded areas downstream, causing the whole town of Moora, about 130 km N of Perth, to be evacuated due to a never before in living memory flood.
During the evening, as if angered by the demise of his sister, he slowed to 15 km/hr, and built strength to be generating gusts of 260 km/hr at 9pm, by then being 460 km N of Karratha and 580 km NNE of Onslow.
By midnight, as if enraged, he had become an extremely destructive Category 5 cyclone, the most intense kind of cyclone, with winds blasting to 280 km/hr, and had slowed to 14km/hr, and was now 430 km N of Karratha and 545 km NNE of Onslow, and, as the formerly stationary High in the southern Indian Ocean began to move rapidly east leaving a trough in it's wake, it looked like he going to swing more to the south, as if determined to leave his mark on that part of the coast.
At dawn on the 21st, he was generating winds up to 290 km/hr, and, although he was still was moving SW at 15 km/hr, he was now one of the most destructive cyclones ever to threaten the Australian mainland.
During afternoon, he had indeed swung more to the SSW, and the authorities undertook a mass evacuation of the town of Onslow, with many residents going to nearby Karratha, as Vance was now packing winds of nearly 300 km/hr and had an estimated 6 metre storm surge, and it was likely that Vance was going to pass close to or enter Exmouth Gulf, and could be just west of Onslow at around noon the following day, around the time of a 7m king tide.
People from outlying properties around the Exmouth Gulf, where there was the possibility of a 8 metre storm surge due to the narrowing of the shallow Gulf towards the southern end, were evecuated to Exmouth.
As evening approached, Vance was 290 km NW of Karratha, 300 km N of Onslow, and 350 km NNE of Exmouth, moving SSW at 15 km/hr, and the winds were gusting to 290 km/hr near the centre, over 250 km/hr out to 50 kms, and over 150 km/hr out to 120 km from the centre, a truly impressive storm by any standards
By midnight, the authorities had closed all roads between Karratha and Carnarvon on the west coast, 550 km to the SW.
A Red Alert had been issued for Karratha, Onslow, and Exmouth, where destructive winds were already being experienced, with a Yellow alert for communities down to Carnarvon, and a cyclone watch extending down the west coast to Geraldton, about 900 km SSW of Karratha and only about 400 km NNW of Perth, and inland to Meekatharra, about 650 km SSE of Karratha.
At 6am on the morning of the 22nd, it looked as if Vance was going to pass between Onslow and Exmouth, and travel the length of the Exmouth Gulf before making landfall at around noon, as it was 245 km W of Karratha, 110 km NW of Onslow, and 130 km NNE of Exmouth, moving S at 20 km/hr.
At 9am Vance was entering the mouth of the Exmouth Gulf, about 65 km west of Onslow, and 55 km NE of Exmouth, moving south at 30 km/hr, with Onslow and Exmouth being buffetted with winds gusting to around 250 km/hr.
At 10:30 am Vance was 30 km east of Exmouth, which was being blasted with winds gusting above 260 km/hr.
Shortly before noon the highest ever Australian mainland wind speed of 267 km/hr was recorded by an official weather station at Learmonth, about 35 kms S of Exmouth.
The previous highest was 246 km/hr at Onslow in 1975.
The Australian Bureau of Meteorology estimates that max. gusts of 280 to 290 km/hr were undoubtably experienced in some areas around the Exmouth Gulf around this time, and, in the vicinity of the cyclone centre, may have reached 300 km/hr!
Vance crossed the coast at the base of the Exmouth Gulf at about noon, with 12 metre seas and a 5 metre storm surge at Onslow, rising along the eastern shore of the gulf to 8 metres on the southern shore, riding on the 7m king tide.
At 1pm, Vance was overland and had weakened to Category 4 gusting to 240 km/hr, and winds were easing in the Exmouth Gulf area.
By 4pm, he had weakened further to Category 3 with winds gusting to 200 km/hr, and was moving south at 30 km/hr.
Winds had eased to 180 km/hr by 9pm, with Vance being 20 km NW of Gascoyne Junction, about 300 kms SSE of the coastal crossing, moving SSE at 35 km/hr, and a cyclone warning was issued for Kalgoorlie, about 1200 kms SE of the coastal crossing.
By 6am on the morning of the 23rd, Vance had weakened to a Category 2 cyclone with winds gusting to 150 km/hr moving SE at 35 km/hr, and a cyclone warning was issued for communities within 180 km of a line from the cyclone centre to Kalgoorlie continuing on to Balladona, about 300 kms beyond Kalgoorlie on Highway 1 near the coast of the Great Australian Bight.
By 9am, Vance had travelled about 700 km overland to be 50 km ESE of Mount Magnet, and had further weakened to Category 1, with gusts to 120 km/hr, and was moving SE at 40 km/hr towards the gold mining town of Kalgoorlie.
At noon, it was 35 km S of Cashmere Downs and 240 km NW of Kalgoorlie moving SE at 50 km/hr.
It was still a Category 1 cyclone and 80 km NE of Kalgoorlie travelling ESE at 70 km/hr by 3pm.
During the evening around 9pm, after having travelled around 1800 kms overland, Vance Catrgory 1 crossed the coast into the Great Australian Bight near Madura, about 600 kms ESE of Kalgoorlie, 1100 kms E of Perth, and 180 kms W of the SA/WA border.
On the morning 24th, the remains of TC Vance generated gale force winds along the South Australian coast, damaging many properties on the Eyre Peninsula, and recording gusts of 120 km/hr at Port Lincoln on the southern Eyre Peninsula.
As the day progressed, a dust storm of around 3 hrs duration with wind gusts to 90 km/hr reduced visibility to a few metres in Adelaide, the Capital of South Australia, and caused traffic chaos.
That night, gale force winds brought down trees and power lines, and caused widespread damage across southern Victoria, with blackouts caused 50,000 homes to be left without electricity in Melbourne, the Capital of Victoria.
TC Vance, the most intense cyclone on record to cross the Australian Coast, certainly left it's mark in Australian history.
The tourist town of Exmouth, population around 2500, with about 780 houses, was devastated, the official SES structural damage estimates being 112 houses destroyed, another 224 severely damaged, and 90% of the houses suffering structural damage.
The houses built by the US navy in the1960's survived better than the rest of the town.
The small fishing village of Onslow, which has the dubious distinction of being the most cyclone prone place on Earth, perhaps faired a little better, although 100% of the houses suffered structural damage
To put this in context, due to it's cyclone prone location, the houses and other buildings in the Exmouth and Onslow area have been built with severe cyclones in mind, however, the severity of TC Vance, with winds gusting up to 300 km/hr blasting the area has certainly put their building standards to the test.
The authorities used hercules aircraft to evacuate all non-essential persons from the Exmouth and Onslow area in order to clean up, as there was no power or water supplies, and vehicle travel in the region was impossible, with helicopters providing the only means of transport.
So widespread was the damage to infrustructure that water supplies were not expected to be restored for at least 2 weeks, and power supplies for at least 3 weeks, and 17,000 litres of bottled water was flown into Learmonth airport on a Hercules.
TC Vance cut a trail of destruction extending right across continental Australia, from the devestation in the NW, down through outback Western Australia, to the relatively minor damage in the southern districts, all the way down to the Great Australian Bight, with the gales continuing along the southern Australian coast beyond Melbourne to the SE corner of the continent.
Vance will long be remembered.
Maintained by Carl Smith.
carls@ace-net.com.au
© Carl Smith 1999 - 2000. All maps, images, and other information on these Web pages is copyright, either by Carl Smith, or by the agencies that produce the satellite images and other weather related information, as indicated in each case. It is essential to obtain permission in writing from the copyright owner before reproducing any of the information on this website in any form whatsoever except for fair purposes of review as permitted under copyright legislation.
DISCLAIMER: Carl Smith is not responsible or liable in any way whatsoever for the manner in which any person, group, or business, chooses to use the information in this website or the consequences thereof. Whilst all due care is taken to ensure the accuracy of the information contained herein, there may be errors, and the information here is not necessarily up to date. All persons are reminded that it is essential to obtain current information from relevent authorities regarding current or potential cyclones.