Month's worth of rain to batter east coast in just three days

East coast residents might want to reshuffle their weekend plans with a month's worth of rain expected to pour down in just three miserable days.

In what is expected to be the biggest rainfall since Cyclone Debbie, the weather bureau has warned Queensland and New South Wales locals about a potentially disastrous low-pressure system.

Bureau of Meteorology Weather Services Manager Richard Wardle said the deluge would hit northern parts of the state late in the week, closer to the weekend.

“Widespread rainfall totals in the range of 100-200mm can be expected with rainfall decreasing as it moves south,” he said.

East coast residents are in for a drenching this weekend. Source: AAP

A months worth of rain is expected to pour down in just three days. Source: AAP

“While there is the potential for riverine and flash flooding, rainfall totals and flood levels associated with this system will be generally lower than those seen with the passage of ex-tropical cyclone Debbie.”

The drenching is expected to hit large areas of Queensland as heavy rain and isolated thunderstorms move across the state from Thursday.

Forecasters claim showers will intensify as a surface trough tracks towards the north Queensland coast from the Coral Sea.

Together, they are set to bring showers across Thursday and Friday and could net a two-day total of 400mm, meteorologist Lauren Pattie said.

Forecasters claim showers will intensify as a surface trough tracks towards the north Queensland coast from the Coral Sea.

Ms Pattie said the area stretching from Cardwell down to Saint Lawrence was most likely to experience deluges - widespread 25-35mm falls with sporadic 200mm downpours - with inland showers also expected.

She said while the 400mm two-day total could eventuate, it was likely to be "very isolated" and fall over higher regions.

The bureau forecasts catchments affected by ex-Cyclone Debbie will see "significantly lower" flood levels than during the disaster.