Parts of Australia are facing "catastrophic" fire conditions over the weekend as a heatwave sweeps across the country and threatens power outages in NSW and South Australia.
NSW, Queensland and Victoria expect extremely hot conditions on Saturday and Sunday with the mercury to climb well beyond 40C in many locations.
The heat is expected to continue throughout the weekend before things cool off early next week.
A state-wide fire ban has been declared for NSW with catastrophic conditions expected on Sunday in the state's central west, across the tablelands to the Hunter region and out to the coast.
The Hunter region will cop the brunt of the extreme heat with Singleton and Cessnock topping the predicted temperatures with 46C on Saturday and 43C on Sunday.
Western Sydney reached 44C on Friday with the city forecast for a cooler 38C. The western Riverina town of Hay reached 47C.
About 11,000 homes and businesses lost power in Sydney's west and fears of more blackouts across the state prompted the NSW government to plead for residents to limit their energy use on Friday afternoon.
Energy provider AGL cut power to an aluminium smelter in the Hunter Valley to supply electricity to nearby schools, homes and small businesses on Friday afternoon.
The Australian Energy Market Operator warned of potential "load shedding" across NSW on Friday to keep the network stable.
But after 5pm the AEMO downgraded its forecast shortfall reducing the risk of blackouts.
Load shedding caused by peak power demand resulted in up to 90,000 homes and businesses being deliberately blacked out in South Australia on Wednesday night.
The AEMO ordered a second generator at Port Adelaide to be fired up on Thursday preventing a second night of outages.
SA Energy Minister Tom Koutsantonis is confident the state will have sufficient electricity supplies on both Friday evening and Saturday but he's still questioning management of the national market over the earlier power cuts.
Mr Koutsantonis says the AEMO had "got caught napping" and "dropped the ball" in its management of electricity supplies.
But Prime Minister Malcolm Turnbull on Friday continued to suggest it was the SA government that had failed to provide backup energy to support its "massive introduction of renewables".
Victorians haven't been spared from the effects of the heatwave with temperatures expected to sit in the low 40s in northern parts of the state on Saturday before cooling down on Sunday.
Conditions are set to be more brutal in parts of Queensland, with the mercury forecast to reach 46C in several southwest towns including Birdsville, which could smash its February heat record of 46.2C on Sunday and possibly break the Queensland record of 46.5C.
Queensland authorities issued warnings about dehydration after three school students were hospitalised north of Brisbane suffering heat-related problems on Friday.
Queensland University of Technology Professor Gerard Fitzgerald urged people to check the colour of their urine to ensure proper levels of hydration.
