Up to 60mm is predicted to fall in Cessnock on Monday, with a further 45-80mm forecast for Tuesday.

The March rainfall record at the Cessnock Airport weather station has already been broken, with the 232.4mm that had fallen up to March 22 exceeding the previous record - set in March 2000 - by 15.8mm.

The Cessnock local government area was declared a natural disaster zone on Saturday; emergency services have advised Hunter residents to delay all non-essential travel, and a severe weather warning remains in place for some parts of the region.

The Cessnock City State Emergency Service unit has had a busy week, with more than 60 callouts during this weather event.

Volunteers have been bunkered down 24/7 at the unit's headquarters since Friday.

Unit commander Jesse Roberts said the callouts have ranged from water threatening properties and damaged roofs to flood rescues - including two medical evacuations, vehicle rescues at Allandale and Murrays Run, a caravan floating away at Maitland, and helping to move 11 horses away from floodwater at Cliftleigh.

Mr Roberts said the unit has worked in collaboration with the Cessnock District Rescue Squad, the RFS, Fire and Rescue, police and the council during the current emergency.

"They have been a huge help - it doesn't matter what colour uniform you wear, it's all about service to the community," he said.

With heavy rain expected up to Tuesday afternoon, the SES continues to urge motorists to never drive through floodwater.

"The key message is 'If it's flooded, forget it'," Mr Roberts said.

Sandbags are available at the SES headquarters on Col Turnbull Drive, Pokolbin, and at the rescue squad in South Avenue, Cessnock for anyone who fears their property may be inundated.

At Weston, Swamp Creek was flowing furiously on Monday morning, and while it had dropped since Saturday, residents were preparing for the worst.

Swanson Street resident Ron Wright - who has experienced through two major floods in the 16 years that he has lived there - has placed markers near the creek showing the flood height at bridge and street level, and this weekend's flood height.

"I warn the neighbours when it reaches this height," he says, pointing to the markers.

Mr Wright said he and his wife Marilyn were prepared for another flood, after their home was inundated in June 2007 and April 2015.

"We have moved everything upstairs ready for the clean-up," he said.

Residents nearby William Street, Abermain and Oliver Street, South Cessnock - where creeks overflowed in 2007 and 2015 - would also be on high alert.

Meanwhile, the SES is advising people in areas low-lying areas of the Wollombi Brook to relocate immediately to family or friends outside the impact area.

The Wollombi Brook at Wollombi is peaking around 7.06 metres with minor flooding, and is expected to remain above the minor flood level (6.7m) during Monday with rises to moderate flooding possible on Tuesday.

The Wollombi Brook at Bulga may reach around 5.5 metres late Monday afternoon with major flooding. Further rises are possible.

Streets in East Cessnock and Kearsley that were impacted by flooding over the weekend have now reopened, but several local roads remain closed on Monday, including:

Stay tuned to Cessnock City Council's website for updates on road closures.

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