It is southern New South Wales' turn for a drenching as the wet weather refocuses today with an east coast low in its midst.
East coast lows are no ordinary storms and have brought disastrous impacts in the past.
The Bureau of Meteorology's Dean Narramore said the system was a continuation of the low seen in south-east Queensland that moved offshore earlier this week.
"It's redeveloped off the coast of NSW and now it's starting to move back towards the Central Coast," he said.
The low is expected to move towards the Central Coast today, but the paths of east coast lows are notoriously difficult to forecast.
Weather warnings for heavy rainfall and damaging winds extend from Newcastle to Bega and included Sydney and Wollongong.
Flood watches are also in place for Sydney's south and warnings are out for abnormally high tides.
So what is an east coast low?
Broadly, an east coast low is a strong low pressure system that develops on or near the east coast of Australia.
But they are different from tropical cyclones, which form over the warmer waters of the north and lows embedded within the westerly wind belt that flows around the Southern Ocean, which tend to scoot through quickly.
East coast lows are particularly dangerous because they often linger along the coast, resulting in long periods of high winds and heavy rainfall.
The impacts are intensified when combined with large swells and high tides.
Wind gusts in east coast lows have been recorded at up to category two cyclone strength.
There are generally a few east coast lows a year, but every few years there is a big one that does a lot of damage.
Past east coast lows
- Sydney to Hobart, 1998: Six sailors died, five yachts sank, more than 60 yachts retired and 55 participants had to be rescued by helicopter. The disaster resulted in a major review of how wind warnings are communicated.
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Pasha Bulker, 2007: As the sun hit the shore, Newcastle residents woke to find a massive coal ship on the beach. The June storm resulted in nine deaths along the Central Coast. The ship was pummelled by waves for three weeks before it was refloated in a salvage operation that cost its Japanese owners $1.8 million.
- April, 2015: Three people died when an east coast low battered Sydney, the Hunter and the Central Coast. At the time, the BOM said gusts reached to 135kph, but the main impact from the storm was the flooding. In a 24-hour period, 119 millimetres of rain was recorded at Sydney Observatory Hill.
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June, 2016: This storm is best remembered for the images of a swimming pool falling into the ocean at Collaroy, Sydney. Five people died during the storm, which brought heavy rain and caused coastal erosion. The impacts were felt from Queensland to Tasmania.
Beachside homes in Collaroy took a battering when the storm swept through. (Fairfax Media: Peter Rae)
So what's the forecast?
Mr Narramore says widespread rain is expected across much of central and southern NSW today and tomorrow as the low feeds moisture onshore.
Even if the low doesn't cross the coast, it is still going to funnel moisture onto the coast south of the system's centre.
"We could see widespread 50 to 150mm, with isolated falls in excess of 200mm possible," Mr Narramore said.
Winds are expected to be in excess of 90 kilometres per hour and could up-end trees and powerlines in the already soggy conditions.
Tides are also expected to be hazardous as the highest astronomical tides of the year combine with strong onshore flow.
Rain could return as soon as this afternoon in northern NSW and south-east Queensland.
But luckily there is not expected to be widespread heavy rainfall, with conditions likely to resemble a more normal Queensland afternoon storm.
Mr Narramore says there will be hit-and-miss showers and thunderstorms, but with catchments already on the edge it won't take much to trigger renewed flooding.
