NSW Deputy Premier and Minister for Regional Transport and Roads Paul Toole said some parts of the state "will receive a month's worth of rain in the next three days", reports Xinhua news agency.

 

"If you are in an area affected by the wild weather, avoid unnecessary travel and never drive through floodwaters," he said.

 

Australia's Bureau of Meteorology (BOM) also issued a warning on Wednesday, forecasting widespread rainfall across NSW and intense rainfall in northern and central parts of the state which could lead to flash flooding.

 

"This is going to be the most widespread and heavy rainfall event we've seen so far heading into summer," BOM senior meteorologist Jonathan How told national broadcaster ABC.

 

Toole said that crews would be dispatched to manage the safety of the state's road network.

 

"We're mobilizing crews to be on standby and ready to respond in areas of most concern to help divert traffic, place signs, inspect assets and carry out a range of other activities to keep people safe and minimize inconvenience," said Toole.

 

State Minister for Police and Emergency Services David Elliott said NSW's State Emergency Service (SES) has already begun responding to an increased number of emergency call outs.

 

The extreme weather system has been forecast to last into the weekend.