By Neve Brissenden

Event organisers across southeast Australia are continuing to sweat over safety concerns and cancellations as an autumn heatwave settles in for the long weekend.

Heatwave conditions were forecast for South Australia, Victoria, NSW and Tasmania from Saturday to Monday.

Melbourne’s famous Moomba Parade was cancelled on Saturday due to concerns for performers and spectators as temperatures soar in Victoria.

“This is a very difficult decision, particularly in Moomba’s 70th year, but we must prioritise people’s health in these extreme conditions,” Melbourne Lord Mayor Sally Capp said in a statement.

“Parade participants are required to spend several hours outdoors in hot, heavy costumes – putting them at greater risk.”

Southwest Victoria was forecast to record its sixth-highest maximum temperatures on record in some areas, with the conditions prompting the Pitch Music and Arts Festival to advise patrons to leave by Saturday morning, and those yet to arrive to stay away.

“If you are arriving on Saturday we recommend delaying your arrival until further notice,” the Pitch Instagram post read.

“The forecast tells us to expect hot weather each day of the festival. In addition, overnights will also be warm.”

Festivalgoers took to social media to express concern, alongside worried family members.

“The amount of people that are smoking using a lighter… all it takes is one cigarette butt to cause absolute havoc,” one commenter said.

“We have decided to go home… I don’t have faith the evacuation plan would be executed correctly… the vibes were down and everyone felt uneasy,” read another.

Golden Plains Festival, held 90km out of Melbourne, has also gone ahead.

A total fire ban was enacted in five Victorian districts on Saturday, with extreme fire conditions forecast to ease on Sunday.

The bureau warned the severe heat was likely to be felt across a large area including Melbourne, Ballarat, Horsham, Warrnambool and Bairnsdale.

Melbourne was tipped to reach a top of 39C on Saturday, while temperatures were set to hit 41C at Warrnambool, Torquay and Avalon.

A top temperature of 38C is forecast for Melbourne on Sunday and Monday.

The state’s central district was slated to reach 41C on Saturday with temperatures of 40C forecast for holiday towns along the Murray River.

Adelaide reached 39C on Saturday, forecast to hit 39C on Sunday and 38C on Monday as the state government activated a code red response late on Friday, with additional services available to people sleeping rough.

Extreme and severe heatwave conditions have also hit Tasmania, with warnings for areas including Burnie, Devonport, Launceston, Richmond, Swansea and Whitemark.

Southern NSW is also experiencing severe heat, with forecast temperatures in the high 30Cs.