Weather pattern is unlikely to hold silver lining to end drought

The ‘neutral’ weather pattern predicted for the months ahead will not bring about much-needed rain to NSW and Queensland.

Children at Narrabeen ocean pool in Sydney on Monday. Picture: John Grainger

Australia is less likely to see the widespread months-long rainfall needed to break the drought, as key climate indicators remain in a “neutral” pattern.

The Bureau of Meteorology says major climate drivers the Indian­ Ocean Dipole and the El Nino-Southern Oscillation are both neutral and are likely to remain­ so until at least June.

Whereas an El Nino weather pattern tends to drive drier weather in Australia, and La Nina can spark widespread, long-term wetter­ weather, the pattern is currently­ neutral.

Bureau of Meteorology meteorologist Grace Legge said that meant the nation’s weather was currently being driven by singular weather patterns, such as the upper low and surface trough that sparked the weekend’s deluge on the east coast.

“This (weekend’s rain) was caused by an upper low that was stalled over NSW, which allows more showers, thunderstorms and rain to develop,” Ms Legge said.

“That, combined with the surface­ trough that sat on the coast, and the moist onshore flow, those things combined to allow the period of significant rainfall.”

But Ms Legge said the record-breaking rain did not necessarily mean enough widespread rain was on the way to end the drought plaguing much of NSW and Queensland.

“When we go into El Nino, we generally see a drying trend, and in a La Nina, we see the opposite, it’s generally wetter over multiple months,” she said.

“But when we’re in neutral, it means we’re less likely to see multipl­e months of above-average significant rainfall over the entire country. That doesn’t mean we can’t see (singular) intense systems that bring the wide falls we’ve seen over the weekend. But we’re less likely to see the widespread rainfall over multiple months.”

The bureau is predicting that daytime and overnight temperatures for autumn are likely to be above average across Australia.

Forecasters are also keeping an eye on Tropical Cyclone Uesi, which is about 250km west of ­Vanuatu and moving slowly south.

The BOM predicts Uesi will keep moving south for the next three days, but may swerve towards­ the east coast of Australia later in the week. There’s a 50 per cent chance it will enter the “eastern region” by Thursday, according to the bureau.

University of Sydney professor of disaster risk sciences Dale Dominey-Howes has warned that the tropical cyclone could ­generate large swells, heavy rain, flooding, and strong winds for the NSW north coast.