Another person has died in the devastating flooding plaguing NSW’s east coast, bringing the current death toll up to four.

The body of a man, believed to be aged in his 70s, was found inside a car in floodwaters north-west of Coffs Harbour on Friday morning.

A passing driver saw the car about 4.30am, police said, which had run off Orara Way at Nana Glen, about 30km from Coffs Harbour.

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“Officers from Coffs-Clarence Police Area Command and SES members attended the scene and found the body of a man inside,” they said.

“He appeared to be the only occupant.”

Police said the man had yet to be formally identified, however, his is the fourth death linked to serious flooding in the area over the last few days.

On Thursday, the body of a 60-year-old woman was found inside a 4WD near Dorrigo.

The woman had earlier contacted police and said she was in trouble on Wednesday night.

A 63-year-old man’s body had earlier been found on a flooded home’s verandah at Moto.

The body of a man believed to be in his 30s was found in floodwaters west of Port Macquarie on Wednesday.

All the deaths will be reviewed by the coroner, police said.

A slow-moving trough, which had delivered intense rain falls to parts of the NSW Hunter region, Blue Mountains and Southern Highlands, is expected to extend further south throughout Friday morning.

“Ongoing moderate rainfall and areas of heavy rainfall are expected during Friday over the Illawarra, South Coast and eastern parts of the Southern Tablelands and Snowy Mountains districts,” the severe weather warning issued by the Bureau of Meteorology read.

“Six-hourly rainfall totals of 60 to 100mm are possible, with 24-hourly totals between 100 and 180mm.

“Rainfall is expected to ease gradually from the north, through the Illawarra and northern portion of the warning area in the afternoon, then through the South Coast and southern warning area in the evening.”

State emergency services have renewed warnings for drivers to avoid crossing flooded roads.

If you are trapped by flash flooding, seek refuge in the highest available place and ring 000 if you need rescue.

-With AAP