Tornado risk for coastal, hills suburbs
15/05/2009
SGIO is encouraging Perth homeowners along the coast and the hills to prepare their homes against the risk of damaging strong winds and tornadoes this coming winter.
SGIO Principal Weather Research Analyst Dr Bruce Buckley said rapid population growth along the coast and in the hills was increasing the exposure of many homes to the impacts of strong winds and tornado outbreaks.
“Points of land that jut out along our coastline and along the Darling Ranges create conditions more favourable to the formation of tornadoes,” Dr Buckley said.
“The Perth metro area and the South West are exposed to sporadic tornado events, typically associated with the passage of cold fronts during the cooler half of the year."
“Once formed, a tornado can produce brief bursts of destructive winds of up to 250km/h along narrow paths, which typically only last for five to ten minutes but during this time can produce damage along paths around 50 metres wide and up to 15km long.”
Dr Buckley said some simple precautions to take if a strong storm was forecast included trimming tree branches close to the home to prevent them from falling on the roof or car and ensuring that outdoor furniture, sheds and BBQs were secured.
The advice from SGIO’s Weather Research Unit, which investigates damaging weather phenomena and explores ways to reduce their impact on WA communities, comes on the fourth anniversary of one of the metro area’s worst tornado outbreaks.
The tornado outbreak on May 16th 2005 damaged homes in Bicton, Murdoch and White Gum Valley, causing property damage to more than 1,400 homes on the day. Bunbury was also badly hit by storms on the same day.
Dr Buckley said that tornadoes in Perth normally followed paths that ran from the northwest to the southeast if formed on or ahead of the cold front, or from the southwest towards the northeast if formed in the cold air behind the front.
“Near coastal suburbs and suburbs in the hills tend to experience the highest number of tornadoes because of their particular exposure to these cold fronts,” he said.
Since 2006 SGIO claims for tornado damage have originated mainly in coastal and hills suburbs including Port Kennedy, Rockingham, Busselton, Australind and Roleystone.
Visit www.sgio.com.au/stormready for information on preparing for storms this winter.