Desperate measures as Epik music festival-goers in Sydney are urged to hydrate for 48 hours beforehand as 'deadly' heatwave looms

People headed for a major music festival this weekend have been warned to properly hydrate themselves up to 48 hours beforehand as a record-breaking heat wave descends on the event.

HSU Events sent out a warning to attendees of the Epik music festival at Sydney's Olympic Park on Saturday, instructing them to hydrate in the two days leading up to the event. 

The festival is set to steam as the city braces for a high of 41C at the time it is scheduled to kick off. 

NSW Health is now on board to help make sure that everyone is safe and several new features including a cool room and misting stations have been added to the venue. 

Meteorologists have warned that forecast temperatures in the state will be the hottest weather since the Black Summer bushfire season in 2019/2020.

HSU boasts that it routinely draws in 20,000 people for its events, setting off alarm bells for organisers looking to avoid a mass onset of heat stroke.

'This weekend is looking like the hottest weather event for an HSU event,' a warning sent out on Thursday read. 

'We will go above and beyond to keep this a great experience, but please know your limits especially in this heat.

'Don’t forget to start hydrating today, what you drink today will benefit you tomorrow!'

Organisers announced the addition of several misting stations and industrial fans being installed inside and outside of the venue, as well as extra water stations. 

Howie Igloo, an indoor cool room, will also provide air conditioning and furniture for attendees which will act as 'the coolest place in the venue', according to the notice. 

In total there will be at least 12 drinking stations littered throughout the venue, according to HSU's map.

The Epik music festival initially went on sale in mid-October and completely sold out within days. 

HSU hosts 10 events across Sydney each year and calls Epik its 'masterpiece'.

Another warning was sent to attendees in the lead up informing attendees that there will be a zero-tolerance policy for drugs on Saturday. 

'There is no such thing as a safe drug so don't take the gamble,' a post on Instagram read. 

'Don't be a mule: There are people that prey on young adults to bring banned substances into events for them. 

'If you get caught you could go to jail, don't do it and don't risk your future.' 

Meteorologists have been warning Sydneysiders this week to prepare for an extreme heatwave this weekend. 

Temperatures in Sydney will reach 39C, Parramatta and Campbelltown will hit 42C and Penrith will reach a sweltering 44C on Saturday.

Sydney's eastern suburbs will be slightly cooler than other parts with highs of 39C on Saturday and 26C on Sunday.

The highest maximum temperature recorded this week was 46.C at Smithville near the NSW-SA border - the hottest air temperature in NSW in three years.

While a southerly change is expected to bring cooler temperatures to Sydney on Sunday, the state's regions will suffer through 40C days well into next week.

NSW Health urged residents to plan ahead and take steps to beat the heat which can particularly affect people aged over 65, babies, young children, pregnant women and the homeless.

Hot weather could put a strain on the body by exacerbating underlying health conditions, NSW Health executive director Jeremy McAnulty said.

'It is important for people to know the symptoms of heat-related illnesses and take precautions to keep themselves and their loved ones cool,' he said.

'If they can, they should also take the time to check on vulnerable and elderly neighbours and family to ensure their safety in the heat.'