Brace yourself Sydney; here come the Wednesday floods

Cassie Trotter/ Getty Images
  • A low pressure system heading east is expected to dump up to 200mm of rain on Sydney on Wednesday
  • The heaviest falls are expected in the morning, with authorities suggesting people reconsider their travel or allow extra time.
  • Flash flooding is expected as the front hits between Newcastle and Wollongong.

Sydney residents should brace themselves for wild weather and flash flooding on Wednesday, November 28, as heaving rainfall and damaging winds hit the region and further south overnight.

The Bureau of Meteorology has issued a severe weather warning and flood watch for the Sydney and Illawarra areas, with up to 200mm of rain expected to fall over the next 24 hours from Tuesday night.

The warning stretches from Newcastle to Wollongong, and as far south as Nowra, along with the Blue Mountains.

A majority of the regions are expected to receive between 50mm and 100mm of rainfall, but an intense band of rain is expected to double that figure, producing nearly 250% of the November average of 83.6mm.

A low pressure system moving from central Australia is expected to intensify as it hits the coast on Wednesday, with heavy rain likely to produce flash flooding in some parts of the Illawarra, Sydney metropolitan, Central Coast and Blue Mountains regions.

The rainfall is expected to ease late Wednesday and early Thursday as the low pressure system moves further offshore, but the system is also expected to bring damaging winds averaging between 60 and 70 km/h with peak gusts in excess of 90 km/h on late Wednesday morning, extending to the Central Coast and the Hunter coastal fringe during Wednesday evening.

The Bureau is warning people to reconsider their morning commute on Wednesday, when then most intense rainfall is expected, with the likelihood of extensive delays amid flash flooding possible.

The NSW SES said it is preparing for the severe weather, with a flood watch issued for the following catchments:

Central Coast (local flooding)
Upper Nepean River (minor to moderate flooding)
Hawkesbury and Lower Nepean Rivers (minor to moderate flooding)
Upper Coxs River (local and riverine flooding)
Colo River (minor to moderate flooding
Macdonald River (local and riverine flooding)
Northern Sydney (local flooding)
Southern Sydney (local flooding)
Parramatta River (local and riverine flooding)
Georges and Woronora Rivers (minor to moderate flooding)
Illawarra Coast (local and riverine flooding)

The flood watch is available here.

The SES said people living and working along rivers affected by the Flood Watch should consider now what they need to do to prepare.

Surf and swell conditions are expected to be hazardous for coastal activities such as rock fishing, boating, and swimming in the following areas.

A hazardous surf warning has also been issued for the Sydney and Illawarra coastlines for Wednesday for people boating, fishing, surfing and swimming.

The flood warning was issued on the same day the NSW government was warning Sydney residents to brace for higher water bills as storage levels at they Warragamba dam continue to fall towards 60%, the trigger level for the city’s dormant desalination plant to kick in and begin converting saltwater into potable water.

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