Five days before Christmas , satellite images showed evidence of a tropical depression in the Arafura Sea, kilometres north-east of Darwin. The following day the Tropical Cyclone Warning Centre in Darwin issued a warning that a cyclone had formed and gave it the name Tracy. At this stage Cyclone Tracy was moving south-west, but as it passed north-west of Bathurst Island on December 23 it slowed down and changed course.
It rounded Cape Fourcroy that night and began moving south-east, with Darwin directly in its path. The first warning that Darwin was under threat came at pm on Christmas Eve when a top-priority flash cyclone warning was issued advising people that Cyclone Tracy was expected to make landfall early Christmas morning.
Despite 12 hours' warning of the cyclone's impending arrival, it fell largely on deaf ears. Residents were complacent after a near-miss from Cyclone Selma a few weeks before and distracted by the festive season.
Indeed in the preceding decade the Bureau of Meteorology had identified 25 cyclones in Northern Territory waters but few had caused much damage. As Kevin Murphy describes in his history of NT tropical cyclones Big Blow Up North: "The residents of [Darwin] could almost have been forgiven for thinking by now that they were invincible. The radius of the galeforce winds extended only 50 kilometres from the eye of the cyclone, making it one of the smallest tropical cyclones on record according to the US National Oceanic and Atmospheric Administration NOAA.
Records show that prior to Tracy, at least six tropical cyclones had severely impacted Darwin. The worst of these was in January when a "disastrous hurricane" nearly destroyed the settlement and 28 people died.
With no cold water to upwell from depth, the slow-moving Tracy quickly intensified. By 24 December, Christmas Eve, it became apparent that the cyclone would not just pass by the city of Darwin, but rather go directly over it.
A storm surge of 4 m 13 ft occurred off the coast of Darwin as Tracy passed, but it did not cause additional flood damage, as the tide was low at that time. On the day of the cyclone, most residents of Darwin believed the cyclone posed no threat to the city.
Cyclone Selma had been predicted to hit Darwin earlier that month, but it instead tracked north and did not impact the area. Despite several warnings, the people of Darwin did not evacuate or prepare for the cyclone and many residents continued with their Christmas festivities. Brunei , Tarakan and Wewak arrived the following week on 13 January.
The ships had brought with them some naval personnel. Working parties were typically composed of 10 or 15 officers and sailors, depending upon the nature of the task. Unfortunately Arrow was damaged beyond repair and was subsequently decommissioned and scrapped.
The raw statistics amply illustrate the magnitude of the relief work undertaken by the RAN. Between 1 and 30 January naval personnel spent 17, man days ashore, with up to ashore at the peak of the operation. Working parties cleared some blocks and cleaned up schools, government and commercial buildings and recreational facilities.
They installed generators, rewired houses, repaired electrical and air conditioning systems, reroofed or weatherproofed buildings, and maintained and repaired vehicles. Some parties worked to save rare plants in the Botanic Gardens. Hygiene parties disposed of spoiled foodstuffs from houses, supermarkets and warehouses.
Female personnel from Coonawarra supported civil relief organisations and manned communication centres. One enterprising sailor from Hobart filled in as a relief disc jockey for the local commercial radio station. The Wessex helicopters transported passengers, ,lbs ,kg of freight and made landings. The HS aircraft completed 14 return flights to Darwin and carried passengers and 50,lbs 22,kg of freight. Like its arrival, the departure of the Task Group was staggered.
Later in the evening, the Darwin meteorological office received an infrared satellite image from the National Oceanic and Atmospheric Administration 's satellite, NOAA-4, showing that the low pressure had developed further and that spiralling clouds could be observed. The storm was officially pronounced a tropical cyclone at around 10 p. Cyclone Tracy was first observed on the Darwin radar on the morning of 22 December.
Over the next few days, the cyclone moved in a southwesterly direction, passing north of Darwin on 22 December. However, early in the morning of 24 December, Tracy rounded Cape Fourcroy on the western tip of Bathurst Island, and moved in a southeasterly direction, straight towards Darwin. The bureau's weather station at Cape Fourcroy measured a mean wind speed of kilometres per hour 75 mph at that morning. By late afternoon on 24 December, the sky over the city was heavily overcast, with low clouds, and was experiencing strong rain.
Wind gusts increased in strength; between 10 p. On 25 December at around a. The highest recorded wind gust from the cyclone was kilometres per hour mph , which was recorded around a. The anemometer wind speed instrument failed at around a. The Bureau of Meteorology's official estimates suggested that Tracy's gusts had reached kilometres per hour mph. The lowest air pressure reading during Tracy was hectopascals 28 inHg , which was taken at around 4 a.
This was recorded during the eye of the cyclone. From around a. After making landfall, Tracy rapidly weakened, dissipating on 26 December. Darwin had been severely battered by cyclones before; in January and again in March However, in the 20 years leading up to Cyclone Tracy, the city had undergone a period of rapid expansion.
Milliken estimated that on the eve of the cyclone there were 43, people living in 12, dwellings in the Darwin area. Though building standards at the time required that some attention be given to the possibility of cyclones, most buildings were not capable of withstanding the force of a cyclone's direct hit. On the day of the cyclone, most residents of Darwin believed that the cyclone would not cause any damage to the city.
Cyclone Selma had been predicted to hit Darwin earlier in the month, but it instead went north and dissipated without affecting Darwin in any way. As a result, Cyclone Tracy took most Darwin residents by surprise. Despite several warnings, the people of Darwin did not evacuate or prepare for the cyclone.
Many residents continued to prepare for Christmas, and many attended Christmas parties, despite the increasing winds and heavy rain. Journalist Bill Bunbury interviewed the residents of Darwin some time later and recorded the experiences of the survivors of the cyclone in his book Cyclone Tracy, picking up the pieces. Resident Dawn Lawrie, a independent candidate for the electorate of Nightcliff, told him:.
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