‘Unseasonable’ cloud band could double monthly average rainfall in areas of central Australia | Australia weather

A large cloud band is set to bring unseasonable wet weather to parts of Australia as it moves eastwards across the country this week.

The Bureau of Meteorology’s forecasts suggest a rain band developing over northern Western Australia on Sunday into Monday will move towards the eastern states over the first half of the week.

Sarah Scully, a senior meteorologist at the BoM, said the rain band had the potential to double the monthly average rainfall in many areas, and could see moderate riverine rises in parts of central Australia.

“What’s unusual is that it is falling over the drier interior of the continent – it is unseasonable for that type of rain band to develop over the area,” she said. “It’s going to fall over areas that [typically] receive very little rainfall in the month of June.”

The rain band is forecast to stretch into southern parts of South Australia on Tuesday, before pushing into New South Wales and south-west corners of Queensland into Wednesday and then continuing to track slowly eastward.

“Once we get to Thursday there’s a lot of uncertainty with the models,” Scully said.

“It’s already been quite a wet month for parts of eastern South Australia and western NSW … Further rainfall is expected in [these] parts of the country.”

The BoM has issued flood watch alerts in Western Australia, the Northern Territory and South Australia associated with the rain band.

Weatherzone meteorologist Ben Domensino said: “While the exact amounts and locations of rainfall are not able to be predicted with high confidence just yet, there is good model consensus that central Australia will see some of the heaviest falls from this system.”

“Widespread rain is also possible in south-eastern Australia.”

Scully said there was the potential for a second rain band to develop over Western Australia and northern parts of the interior again on Thursday.

Possible snowfall top-ups

The Australian alps in the country’s south-east may see “further snowfall top-ups” this week as a series of cold fronts pass through the region, keeping temperatures below average in the south-east.

“On Wednesday into Thursday there is a cold front that will sweep across south-east Australia that will join up a bit with the moisture from the cloud band,” Scully said.

Scully said while heavy dumps in the mountains were not forecast, there were chances the system would “continuously top up what is already there” throughout the week, bringing welcome news for the skiing industry after major resorts in NSW delayed their start to the winter season.

Scant snow cover led Perisher, Thredbo and Selwyn resorts to limit their operations earlier in the month.

In Victoria, after heavy falls in the last fortnight, the natural snow depth at Mount Hotham was 59cm on Sunday, 20cm higher than the three-decade average for this time of the year.

Unusual heat in the north-east

Meanwhile, in the country’s north, unusually warm temperatures in Queensland and the Northern Territory are set to continue until midweek, according to the BoM.

“Both minimum and maximum temperatures there are really well above average – between 6C up to 10C above average,” Scully said.

The higher than usual temperatures may be the result of active thunderstorms north of Australia, which drag latent heat into the atmosphere over the country.