Australia is experiencing a range of weather extremes, from giant hail and severe storms in the east to blistering heat and code red warnings in the south.
The contrasting conditions are caused by a massive storm system stretching from central Queensland to Tasmania, and a prolonged heatwave affecting South Australia.
Storms and Floods In East Coast
Parts of NSW, Queensland and Victoria have been battered by heavy rain, flash flooding, damaging winds and large hail in the past few days.
The Bureau of Meteorology (BoM) warned that the thunderstorms could produce 'large to giant hail', which is more than 5cm across and bigger than golf balls.
Some areas also recorded more than 100mm of rain in 24 hours, causing rivers to overflow and roads to close.
The stormy weather is expected to continue until the weekend, as the system moves eastward along the coast.
The BoM said that the storms are tapping into the extra moisture from the Eastern Australia Current, which is flowing straight down the coast and making the waters warmer than normal.
This is partly influenced by the La Niña phenomenon, which typically brings more rainfall and cyclones to eastern Australia3.
Storms Wreak Havoc on the Gold Coast
The Gold Coast was hit hard by the storms that swept across the state on Christmas Day, leaving many homes without roofs, power or water.
Denis Fogarty, a resident of Nerang, said his house was "totally destroyed" by the storm, which tore off his roof and insulation.
He said he was grateful for the help of the ADF, who arrived on Wednesday to clear the debris and secure his property. "They've been absolutely fantastic," he said. "They've done a wonderful job."
The ADF has deployed about 100 personnel and 40 vehicles to the Gold Coast, as part of Operation Queensland Storm Assist.
The operation is led by Brigadier Jason Blain, who said the ADF was working closely with the local authorities and emergency services to provide support. "We're here to help the community get back on their feet as quickly as possible," he said.
Also Read: Cold Front to Bring Potential Severe Weather Hazards in Western Australia This Week: BOM Warns
Cyclone threat looms over the north
While the south-east is recovering from the storms, the north is bracing for a potential cyclone.
The Bureau of Meteorology (BoM) has issued a cyclone watch for parts of the Cape York Peninsula, as a tropical low intensifies in the Coral Sea.
The low is expected to develop into a category one cyclone by Friday, and could bring damaging winds, heavy rain and flooding to the region.
The ADF is also ready to respond to the cyclone threat, if needed. Brigadier Blain said the ADF had pre-positioned personnel and equipment in Cairns and Townsville, and was monitoring the situation closely. "We have the capability and capacity to provide assistance to the communities in the north, if required," he said.
Heatwave and code red in the south
While the east coast is soaked, South Australia is sweltering under its longest burst of extreme heat for more than three years.
Temperatures across the state are set to surge into the mid-40s in some regional centres, with Adelaide forecast to reach 41°C on Friday.
The state government issued a code red, which is activated when extreme weather is on the way and aims to reduce the harmful effects on people sleeping rough.
Those who are homeless will have access to emergency accommodation and services during the four-day code red period.
The heatwave is caused by a high pressure system over the Tasman Sea, which is blocking any cool changes from reaching the state.
The hot and dry conditions also increase the fire danger, especially in the north and west of the state.
The BoM advised people to stay hydrated, avoid exposure to the sun, and check on their neighbours and pets.
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