Rain drenches Sydney after wreaking havoc on NSW South Coast

A downpour heading towards Sydney has caused chaos on the NSW South Coast, unleashing more than 250 millimetres of rain on beach hamlets and flooding roads and houses.

Some residents of the South Coast were preparing to evacuate on Thursday evening, with the heavy rain that began to fall overnight coinciding with a very high tide. No evacuation orders had yet been issued by 10pm.

The extreme weather prompted the Bureau of Meteorology to issue a severe weather warning for parts of Sydney as well as the Illawarra, South Coast, Central Tablelands and Southern Tablelands, predicting heavy rainfall and flash-flooding through to Friday afternoon.

The worst of the rain affected the southern and south-western suburbs in Sydney. Moderate flooding was possible in the Hawkesbury Nepean Valley and on the Georges and Woronora Rivers.

At 10pm, the SES had issued advice warnings to Windsor and surrounds, Menangle and surrounds, Penrith and surrounds and North Richmond and surrounds. Residents in all areas were warned of minor to possible moderate flooding.

Rainfall of about 105 mm was recorded in the 24 hours to 8pm on Thursday around the Hawkesbury Nepean Valley. Sydney Airport had recorded more than 43.4 millimetres of rain since 9am.

The bureau had said earlier on Thursday that up to 150 millimetres could fall within six hours, and up to 250 millimetres over 24 hours, as the weather front moved through.

The Shoalhaven region has been the worst affected area so far, with the coastal village of Currarong, near Jervis Bay, recording 265 millimetres of rain since 9am on Wednesday – about twice its average for the month.

On the southern side of the bay, Vincentia received 248 millimetres since 9am on Wednesday, while nearby Nowra has recorded 176 millimetres.

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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