A reprieve is on the way for flood-hit communities in New South Wales with the Bureau of Meteorology forecasting sunshine and easing conditions for the rest of the week.
More evacuation warnings were issued on Tuesday as much of the Australian state – in addition to areas of Queensland, Victoria, Tasmania, South Australia and the ACT – continued to receive heavy rainfalls.
Some 18,000 residents in NSW had already been displaced by the flooding with another 15,000 readying themselves to evacuate as authorities warn flood waters may not abate for days.
Jordan Notara, a senior forecaster at the bureau, said the weather at least looked set to “flip heading into the rest of the week”.
“The weather for Wednesday is going to be vastly different to what we’ve been seeing over past days,” he said. “Rainfall generally will be confined to some areas of our western plains and it really is going to be lighter in nature.”
Notara said there was still some rainfall expected, around Thredbo, but that would amount to just 20mm to 30mm. Light showers could also hit the northern slopes. “The temperatures are also on the increase with clearer skies and generally sunny conditions across vast areas of the state.”
The NSW premier, Gladys Berejiklian, said on Tuesday the weather event had been “catastrophic”. “This is a weather incident beyond anything we could have comprehended,” the Liberal leader said.
Major flood warnings were issued by the SES for the Orara, Hawkesbury, Clarence, Upper Macintyre, Severn, Gwydir and Mehi rivers; with evacuation warnings issued for residents along the Hawkesbury, in Singleton, Southgate and for the Picton CBD.
About 500 people in 200 homes were ordered to evacuate on Tuesday with boats and helicopters employed to help residents leave. Some water levels were expected to rise overnight into Wednesday. The bureau said not all flood waters had peaked.
“The flood situation remains a serious threat to life and property across NSW and will continue to cause significant disruption and isolation,” the bureau said in a statement. “Residents and visitors in affected areas are urged to closely monitor warnings and updates over coming days.”
Following days of wet and dreary conditions, Sydney is forecast to have a high of 30C on Wednesday. Notara said winds coming in from the west were dragging the warmer weather across the state, clearing skies and providing an opportunity for flood-hit regions to assess the damage.
He also said that the trough that brought some of the extreme weather had shifted out to sea – but that didn’t necessarily mean there would be no further weather warnings for NSW.
The bureau expects strong winds in the southern tablelands, south coast, Illawarra and parts of the central tablelands – which could cause hazardous conditions and result in further severe weather warnings.
Experts say it’s unusual to see so many places with such high rainfall across such a wide area.
The extreme rainfall came after three weather systems combined, and fell on already saturated ground due to a wetter-than-average summer, thanks in part to the La Nina weather pattern.
A warmer atmosphere can hold more moisture - about 7% for each degree of warming - so there's more available to fall as rain. If you do the maths, Australia has warmed by 1.4C, accounting for roughly 5-10% of the rain.
But climate scientists say it's not that simple because of the many different factors that influence rainfall. Climate change could also be making weather patterns that deliver downpours more frequent, but again, more research is needed.
Winds could reach in excess of 90 km/h and are forecast to increase across Wednesday before easing by the evening.
Notara said such conditions marked the end of the weather event and the state was on the “cusp” of the rain retreating. On Tuesday, Mount Darragh, Bodalla and Barlows Bay all recorded more than 110mm.
In Moree, where an evacuation warning was issued by the NSW State Emergency Service by the afternoon, residents saw over 150mm of rain before 9am.
More than 10,000 requests for help had been made in NSW since Thursday with emergency services performing about 900 flood rescues.
WaterNSW announced spills coming out of the Warrangamba Dam had halved from their peak on Sunday. The daily total of water spilling from the dam has fallen to 240 gigalitres – just below half the 500-gigalitre peak on Sunday.
In a statement, WaterNSW said that while rain continued to fall in the catchment, inflows had fallen to 140G/L a day, well below projections.
Many communities were still stranded or affected by the flooding, with authorities working to get supplies and groceries to those cut off by flood waters.
Earlier on Tuesday, the federal minister for emergency management, David Littleproud, said Coles was working to airlift supplies to its North Richmond supermarket to alleviate shortages.
“They intend to helicopter goods into North Richmond’s store this afternoon, as soon as arrangements can be made we will continue to make sure that mechanism is worked through in every community where there are shortages, where we are unable to get trucks or boats across to support these communities in their hour of need,” Littleproud said.
He also said that the government was working with NBN and Telstra to make sure telecommunication services were restored to these communities as soon as possible.
The prime minister, Scott Morrison, had earlier announced the federal government had received a request for 1,000 ADF personnel to help with the clean up in NSW. “We want it to be done swiftly and effectively to try and get these communities back on their feet as quickly as we possibly can,” he said.
