Greater Sydney will get a preview of the horrendous rain lashing the Hunter Region when showers begin to move down the coast on Thursday night, paving the way for a biblical downpour on Saturday.
Some areas of the Hunter Region were pummelled by 100mm of rain in extreme bursts on Thursday, prompting the Bureau of Meteorology to issue a flood warning.
Port Stephens Council shared an image on social media of a road broken apart under the pressure of the heavy rain and flood waters.
Sydney will get a glimpse of that on Thursday night with continued showers predicted, predominantly in the northern part of the city.
There is also a minor flood warning for southern Sydney, the Georges River and parts of the Illawarra.
“We are expecting the rain to really pick up on Friday but tonight we should see 5mm to 20mm through the Sydney basin,” BOM duty meteorologist Helen Kirkup told NCA NewsWire.
“That’s on top of what we already had before 9am, which was 15mm in most areas and in Hornsby it was 28mm before 9am.
“We could easily see another 20mm (on Thursday night) and it is coming in from the north, so the heaviest rainfall should be felt around the northern beaches.
“Terrey Hills has already seen a lot and the CBD and south Sydney should also get a fair bit of rain, possibly some lightning as well.”
Ms Kirkup said while rain on Friday would be heavy, Saturday could be dangerous, with some areas of greater Sydney a chance to be lashed by 200mm of rain.
“On Friday, there is a chance we could see 20mm to 50mm (in some regions) and within that there is always a chance isolated locations could see even more,” she said.
“When we get to Saturday, the worst will shift to the south and we will see between 50mm and 100mm. It is not out of the question that some areas could see 200mm.
“What‘s up north now in the Hunter is shifting to Sydney and it could cause quite significant problems.”