Tropical Cyclone Rusty

Landfall | Summary
Posting Date: February 27, 2013, 12:00:00 PM

Forecast Track and Intensity With 1-minute sustained winds of 136 km/h and gusts to 170 km/h, Rusty came ashore as a severe tropical cyclone—a category 3 storm by the Australian system of cyclone classification (approximately equivalent to a category 1 storm on the U.S. Saffir-Simpson Scale). Rusty made landfall in Pardoo, which is located approximately 110 kilometers east northeast of Port Hedland. Rusty is weakening as it moves further inland, but wind gusts of 165 km/h were still expected near the center of the storm overnight as well as widespread heavy rainfall overnight and on Thursday. Cities and towns in the path of the storm will experience destructive winds overnight, including gusts in excess of 125 km/h. These winds should reach Marble Bar by early Thursday with gale-force winds extending further inland to Nullagine and possibly Newman and Telfer. Widespread flooding, which is exacerbated by Rusty’s massive size and slow movement, is also expected in both the Fortescue and DeGrey catchments in Pilbara coastal streams. Today’s high tide could also bring damaging waves to coastal areas between DeGrey and Wallal. Rusty is expected to weaken below cyclone intensity overnight Thursday. Reported Impacts Although Rusty did briefly intensify to a category 4 storm about 10 hours prior to landfall, it did not maintain that strength. Rather, as Rusty approached shore, the eyewall weakened right around landfall. In addition, the trajectory was more southward than southwestward, as was originally forecast. These developments in the evolution of Rusty, plus having a small radius of maximum winds of 38 km, spared Port Hedland from a more destructive situation. Still, there have been reported wind gusts over 100 km/h in Port Hedland along with about 100 mm of rain thus far. While the wind intensity at Port Hedland was not as great as feared, the duration of the winds has been significant, as Port Hedland has received gale force gusts for more than 36 hours—an all-time record. The deputy mayor of Port Hedland described the wind and accompanying rain as being relentless for the past couple of days, but thus far the only damage reported is downed trees in Port Hedland. In advance of the storm, more than 300 Port Hedland residents were evacuated. Port Hedland also closed schools and three main iron ore ports in the Pilbara region, home to the world's largest source of iron ore. Australia’s Department of Fire and Emergency Services issued a red alert for Pardoo and nearby Whim Creek. A red alert means that residents should take shelter and remain inside. The red alert is expected to remain in effect until Friday. Pardoo saw wind gusts to 165 km/h and has already received nearly 500 mm of rain. Damage reports thus far include a leaking roof and minor damage at Pardoo Station. Storm surge also occurred in the DeGrey-Pardoo area. Exposure at Risk Most residential and commercial structures in the Port Hedland area should withstand today’s storm with very little damage as these structures performed well during Tropical Cyclone George in 2007, when wind gusts reached 200 km/h. Fewer than 2% of buildings sustained damage as a result of George’s force, and most of these buildings proved to have weaknesses due to poor maintenance. Still, Port Hedland has a number of trailer (caravan) parks for visitors and residents, and these structures are particularly vulnerable to damage. Also, if there is damage to residential structures, it will likely be to roofing, as residential roofs are typically made of metal and are thus susceptible to wind damage. Prior to storms’ arrival on the Western Australia coast, commercial/industrial facilities usually secure their structures and contents from damage. In advance of Rusty’s arrival, the ore-exporting ports at Port Hedland, Port Walcott, Dampier, and Cape Lambert were closed. Mining operations inland and offshore oil and gas production also ceased in good time, and workers were evacuated. Given these advanced preparations, most commercial/industrial facilities should fare well in today’s storm. However, commercial and industrial buildings constructed of light metal framing will be the most susceptible to wind damage. AIR does not expect significant insured losses from this event, primarily because of the region's relatively sparse population, stringent building codes, and preparations made in advance of the storm. No other cyclones are expected to develop or impact the western region of Australia in the next few days.

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Posting Date: February 27, 2013, 12:00:00 PM