A powerful weather system is expected to drench and batter New South Wales and eastern Victoria this week as a low pressure area intensifies off the east coast.
Days of persistent rain, strong to damaging winds and dangerous ocean conditions were forecast for NSW and Victoria’s Gippsland region from Monday evening, according to the Bureau of Meteorology.
The bureau said a predicted vigorous coastal low was expected to deliver persistent rainfall on Tuesday and Wednesday. Totals could reach 50 to 150mm in 48 hours, with some places expected to record more than 200mm.
The heaviest falls were expected for the NSW Central Coast, including Sydney and the Hunter regions, as well as parts of the Illawarra and south coast, said a senior meteorologist, Angus Hines. But it would only take a “subtle shift” to send the rain north to areas that were “extremely sensitive to rain”.
“One area which we’re watching really closely is the mid north coast of New South Wales, because this area is still recovering after record rain and record flooding during May.”
Riverine and flash flooding was a “distinct possibility”, Hines said.
Strong to damaging wind gusts would also become widespread, affecting the east coast from southern Queensland to eastern Victoria.
“Winds of this strength are certainly strong enough to bring down trees and branches, damage property and cause power outages,” Hines said.
Sustained winds of 40 to 70 kilometres an hour were expected, with gusts up over 125km/h possible.
Conditions were expected to be treacherous on the water, with the potential for waves up to seven metres, and could cause coastal erosion and possible inundation of low-lying areas along the eastern foreshore, he said.
“This coastal trough is deepening off the north coast. It’s expected to evolve into multiple low pressure systems off the coast tonight,” the bureau’s hazard preparedness manager, Steve Bernasconi, said. “One of these low pressure systems will start to dominate, and that will become then a vigorous coastal low.”
It was complex system, he said, which involved multiple low pressure systems combining and interacting. It was also dynamic, and if the pressure dropped quickly, could turn into a more significant coastal low system.
The NSW State Emergency Service was urging people to be vigilant, and to prepare by tying down any loose items, to avoid them becoming projectiles.
“We are encouraging communities to start preparing their homes,” said SES deputy commissioner, Debbie Platz. “It’s really critical that you clean your gutters, that you move items that are loose … such as trampolines and outdoor furniture, tie them down or move them to a secure location.”
“Please move any vehicles that you have away from any large trees,” she said.
Platz said the SES had already deployed vehicles, helicopters and personnel to areas likely to be heavily impacted. “We have already pre-positioned 395 of our amazing volunteers on the ground throughout our northern metro and southern region areas.”
An assistant commissioner, Allison Flaxman, said destructive winds and flash flooding were a significant risk.
“If you do come across flash flooding while driving, do not take the risk of driving through flood waters,” she said.
“It doesn’t take much water to move your vehicle, and you don’t know what damage has been done to the road surface underneath the flood waters.”
On Tuesday, Sydney residents could expect rain and wind with maximum temperatures of 16C (minimum 11C), and a top of 14C and possible showers in Melbourne (min 4).
On Wednesday, Sydney’s forecast was max 17C, min 11C, and Melbourne’s was max 13C, min 6.
