“Consecutive La Niña's have resulted in Australia's wettest two year period on record and the heavy rains should continue through autumn 2012,” says Tom Saunders, Senior Meteorologist at the Weather Channel.

“So far this year widespread flooding has already crippled southern Queensland and northern New South Wales. As the current La Niña weakens it was initially expected our rainfall patterns would return to normal by the middle of autumn,” he continues.

“However, a new pattern of abnormal sea surface temperatures has developed to our west with a record warm Indian Ocean. This indicates that southern Australia will face a wet autumn,” says Saunders.

“The warm waters will increase evaporation and the transportation of moisture into the atmosphere. The moisture will then be blown over southern Australia by westerly winds and cause an increase in both cloud and rainfall,” Saunders continues.

“The states most likely to be affected will be South Australia and New South Wales. Northern parts of Australia can also expect above average rain this autumn as the weakening La Niña continues to dominate our weather over the last months of the tropical wet season.”

“With no reliable method of predicting when the Indian Ocean will cool down it is too early to make a call on winter rainfall for the nation,” he concludes.