Sydneysiders could cop a month's worth of rain in one day on Tuesday with what’s been dubbed a potential “bomb cyclone” drenching the city.
Some parts of the city, including Rose Bay and North Ryde, have already received more than 30mm of rain in the 24 hours leading up to 10am Tuesday, according to the Bureau of Meteorology.
It doesn’t appear that will be the end of it either. Widespread rainfalls of 30-50mm are expected over the 48 hours from Tuesday, BOM meteorologist Miriam Bradbury said, with up to 90mm possible in some areas including the Hunter, Sydney and Illawarra coasts.
Ms Bradbury added some areas along the Sydney coastline could receive 60-90mm over the same period with Metro Sydney looking at 50-70mm.
BOM forecaster Hugh McDowell told NCA Newswire Sydney could be looking at "almost a month‘s worth of rain in one day".
A severe weather warning has been issued for a swathe of the seaboard between Gosford on the Central Coast to Batemans Bay on the south coast
NSW coast to cop 90km/h wind gusts
Damaging winds gusts in excess of 90km/h are possible from late Tuesday onwards, the bureau warned, along with hazardous surf and coastal erosion.
Heavy rain and thunderstorms are also likely across the area.
Weatherzone meteorologist Ben Domensino called it a potential “bomb cyclone” if the cold front, which is moving from the west causing all the rain, pressurises as it develops into a low.
“Bomb cyclones have been known to cause a rapid onset of severe weather when they form close to the coast,” he said.
'Rapidly developing beast' off the coast
A "bomb cyclone" is one of a few names given to the system. A "weather bomb" is another description.
7News meteorologist Jane Bunn highlighted the colourful names the weather system has been given, referring to it as a "bombing low" or an "explosive cyclogenesis", which is also another name for a weather bomb.
"Either way, it's a rapidly developing beast, just off the coast," she tweeted.
Conditions are expected to ease Wednesday as the system moves offshore.
'Mini-tornado' a cause for investigation
Inland areas haven't been spared the wild weather, with extreme wind — described as a mini-tornado by locals — ripping the roof off a house in Orange in the central west.
Mr McDowell said the bureau is investigating what caused the freak weather event.
"The maximum winds recorded in Orange, on our observations, was 28 km/h, so it looks like it was a very localised, small scale event," he said.
Damaging winds gusts in excess of 90km/h are possible from late Tuesday onwards across the state, Mr McDowell warned, along with hazardous surf and coastal erosion.
Record winter warm run comes to an end
Tuesday’s cold front brings to an end a new winter record of 15 days above 20 degrees in Sydney.
"Maximum temperatures will plummet in the wake of the front, in parts dropping by up to 12 degrees," Ms Bradbury said.
"After balmy 27 degree day (on Monday), Sydney can expect a much cooler and rainier 16 degrees (on Tuesday)."
Mr Domensino tweeted the previous record run for Sydney winter was 10 consecutive days above 20 degrees.
“This record was likely caused by a combination of persistent high pressure over southeastern Australia and a warmer climate,” he tweeted.
The rest of the week will be somewhat cool for Sydney too with tops between 17 and 18 forecast up until the start of next week when temperatures will rise to maximums in the mid to low 20s.
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