Severe storms, heavy rain and rising flood risks are sweeping across south-east and central Australia as a deep low-pressure system powers east over the next three days.

Bureau of Meterology Senior meteorologist David Crockett said the low would drive widespread rain and storms over the next three days as it tracked from South Australia into NSW, Victoria and Queensland.

“We will see a big low-pressure system bringing rain and storms across a vast area of south-east and central Australia over the next three days or so,” he said on Monday.

The system developed over Western Australia on Saturday and has already delivered widespread rain and thunderstorms across the west, western SA and the southern Northern Territory, including up to 30 millimetres in Alice Springs on Sunday.

The low was centred in far-west SA on Monday, spreading rain across the state with a risk of severe thunderstorms and damaging winds in SA’s north and into the southern NT.

As the system tracks east, it will move over the Eyre and Yorke peninsulas before passing near Adelaide and the hills, with higher totals possible over already saturated catchments.

“Many of those areas, particularly the Adelaide Hills, are quite wet already following recent rain … the creeks and rivers are ready to respond quickly to any further rainfall,” Crockett said.

The rain band is expected to shift into western NSW and much of Victoria from late Monday and into Tuesday, with the heaviest falls of 40-60 millimetres expected early on Tuesday over the north-east Victorian ranges and the south-east ranges of NSW, particularly the alpine regions.

By later Tuesday and Wednesday the focus turns to eastern NSW and south-east Queensland, which can expect generally 5-15 millimetres, with higher totals along the NSW ranges.

“This could be the first severe storm of the season for some of those areas, depending on how the storms develop on Tuesday afternoon,” Crockett said.

Forecasters warn of a broad severe thunderstorm threat on Tuesday afternoon from northern Victoria through western NSW into south-western Queensland, with heavy rain, damaging winds and possible large hail.

There are warnings for the Avoca, Loddon and Murray rivers around Barham, with saturated catchments primed to respond quickly to further rain.

A flood watch covers most northern Victorian catchments, where rivers could rise rapidly from Tuesday morning.

-AAP