from the bom website -http://www.bom.gov.au/announcements/media_releases/wa/20111017.shtml
Communities in WA's north-west urged to prepare now
The Bureau of Meteorology has issued its tropical cyclone seasonal outlook today, and is urging communities in WA's north-west to prepare now for the coming wet season. The call comes as the Bureau and Fire and Emergency Services Authority (FESA) begin a tour of the north-west of the state to promote cyclone and flood awareness initiatives.
Bureau of Meteorology WA Regional Manager for Severe Weather Services, Andrew Burton, said with the wet season rapidly approaching, it is important that residents start preparations immediately. Every season brings the risk of wind damage, flooding and isolation and there is simply no room for complacency.
"Climate models are trending toward another La Niņa episode, which would lead us to expect a slightly higher than average number of tropical cyclones, however, no two La Niņa events are the same. While this La Niņa may be weaker than the last, this doesn't mean Western Australia can expect fewer tropical cyclones than the previous season," said Mr Burton.
Coastal communities between Broome and Exmouth face the highest cyclone risk of any region in Australia, where we would expect around two coastal impacts with one of those likely to be severe. This is what everyone in the north-west needs to be prepared for from the start of the season (1 November).
"For most people a bad season is one when their community is directly affected. Last season's severe flooding in the Gascoyne was not directly associated with a tropical cyclone, but is an example of how tropical lows can also cause significant flooding," said Mr Burton.
In terms of cyclone numbers, last season was average. There were five cyclones in waters off the north-west Australian coast, and no severe wind impacts with the exception of a tornado which ripped through Karratha's central business district as Tropical Cyclone Carlos approached. Last season's intense La Nina produced a higher than average number of tropical lows, while these didn't intensify into tropical cyclones, they did threaten the north-west coast causing disruption to communities and in particular to industry.
Summary tropical cyclone seasonal outlook for north-west Western Australia
A 60% chance of an above average number (40% chance of a below average number) of tropical cyclones in waters off the northwest coast (where the average number is five).
Likelihood of around two coastal impacts with a significant risk of at least one severe tropical cyclone coastal impact during the season.