Roads are flooded and closed, and fast-moving water has washed away some sections of road surface. Fallen trees have also closed roads.

On Thursday afternoon, the State Emergency Service issued a “watch and act” flood warning for parts of Sanctuary Point, warning residents to prepare to evacuate because flash-flooding from a nearby creek is likely to combine with the evening high tide.

It has also issued a “watch and act” for low-lying areas near the Wollondilly River in Goulburn.

So far, the SES has carried out 13 flood rescues, mostly for people from cars caught in floodwaters in the Shoalhaven area, as well as a person in waist-deep water in a backyard near Goulburn.

It has responded to 230 jobs since 5pm on Wednesday, including for damaged roofs, fallen trees and flooded homes, with 166 of those jobs in the south-east zone that encompasses the South Coast, Illawarra and Southern Tablelands.

“We are expecting the conditions could be severe overnight as well,” spokesman Ben Deacon said. “The event isn’t over yet.

“The bureau has advised us to monitor this closely, as these systems can be volatile and conditions can change at short notice.”

The bureau said catchments were already relatively wet after recent rainfall, which increased flood risk.

It has also issued minor flood warnings for the Cooks River at Tempe Bridge, and for Sussex Inlet and St Georges Basin on the south coast, to coincide with Thursday evening’s high tide.

Meteorologist Gabrielle Woodhouse said the rain in Sydney would probably get heavier moving in to the early hours of Friday morning.

“The rain in Sydney has really only just started to develop, and similar to what we have seen in parts of the Illawarra, it will probably fill in a bit and be fairly steady, and later [on Thursday] or more likely overnight, we’ll see heavier rainfall develop.”

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