The Bureau of Meteorology (BOM) has said there will be no let up from the heatwave conditions until at least the weekend with temperatures in many cities expected to soar into the mid-40s.

It’s actually forecast to get hotter than previously expected in some places with police in New South Wales saying there could be deaths if people are irresponsible in the heat

and South Australia declaring a “Code Red” heat emergency for the most vulnerable.

The elderly and homeless are susceptible to the conditions but just the sheer length and intensity of the heat could put anyone at risk with warnings to avoid “strenuous activity” and to stay hydrated.

Adelaide, Canberra, western Sydney and regional areas of New South Wales and Victoria are particularly at risk. The capital is suffering through its most intense heatwave for five years.

While temperatures in Sydney’s western suburbs could be up to 16 degrees hotter than at the beach. On Friday, Bondi could struggle to get to 30C while Penrith will soar to 45C.

“This heat is already record breaking, with Borrona Downs, in far north west NSW, recording the state’s hottest minimum temperature for any month,” said Sky News Weather channel meteorologist Rob Sharpe.

The mercury only dropped as low as 34.6C on Sunday, beating the previous record of White Cliffs set in 2017 of 34.2C.”

EXTREME HEAT

A heatwave has enveloped all of south east Australia and much of the centre of the country stretching into southern Queensland. An “extreme” heatwave, that can pose health risks to even fit people, is growing over eastern NSW.

Daytime temperatures of up to 12C above average and 10C higher than usual at night are expected until Friday.

Sydney’s CBD will see today’s 30C creeping up to 34C on Friday with night time lows as high as 24C. Penrith will be 41C today reaching 45C on Friday.

Inland, Dubbo could see 45C on both Wednesday and Thursday, Wagga is facing four days above 40C and Broken Hill could reach 46C on Thursday. Costal areas should be cooler.

Canberra is looking at 39C today and then three days above 40C.

“The heat will build through this week and people are warned they should not expect a reprieve until at least the weekend in many areas,” the BOM New South Wales said in a statement on Tuesday.

“Heatwave conditions can also have a significant impact on people’s health and the community is warned to avoid strenuous activities where possible, remain hydrated and check on the safety of older or vulnerable members of the community.”

NSW Police Deputy Commissioner Jeff Loy said people should call triple-0 if they spot others in distress.

“As the weather heats up, I cannot stress strongly enough to motorists that it’s not only an offence for children or pets to be left unattended in a vehicle, it can be deadly.

“It can be just as dangerous to leave the elderly and disabled members of the community in cars during days of extreme heat.”

He also advised sunseekers to be careful in the water following a spate of drownings in the state.

Scorching over most of #SouthAustralia today Adelaide hit a top of 40°C and it's even hotter in the north. This police patrol at Marla unofficially recording 46°C on the car thermometer, Maree hit 48°C! Stay safe in the heat @CFSAlerts @SAHealth @SAPoliceNews #FeelingHot2019 pic.twitter.com/8c2wm1QnAu — Bureau of Meteorology, South Australia (@BOM_SA) January 14, 2019

A hot air mass over the interior of #WA will migrate across to southeast #Australia over the coming days. Hot days and warm nights ahead for those areas. For latest forecast and warnings visit https://t.co/4W35o8i7wJ pic.twitter.com/LfwdbhnhBG — Bureau of Meteorology, Australia (@BOM_au) January 12, 2019

CODE RED DECLARED

In Adelaide, the State Emergency Service has issued an extreme heatwave emergency warning and the state government has declared a Code Red for Tuesday and Wednesday as temperatures soar towards the high 40s in some parts of the state.

The Code Red triggers extra funding so services for the homeless can be extended while a special phone line will also operate for the next two days, providing regular checks on the elderly and others at risk from the extreme conditions.

Adelaide will see a 41C max on Tuesday than 40C on Wednesday and an only slightly milder 37C on Thursday. Some nights this week might not get cooler than 24C.

The top in the city on Monday also hit 40C while in northern centres like Marree it climbed to 48C.

Premier Steven Marshall has urged South Australians to take care during the very hot days and stay out of the sun as much as possible.

“These are extraordinary temperatures that are forecast this week,” the premier said.

Mr Sharpe said hot air from central Australia was funnelling its way down to the south: “A severe-to-extreme heatwave has been occurring over the southeast interior for a few days already, but today it is spreading to Adelaide, inland Victoria and parts of Tasmania. From Tuesday it will include Sydney and pretty much all of New South Wales as it intensifies in the ACT.

“This is getting into very hot territory and that heat just lingers.”

MELBOURNE: PLACE TO BE

Melbourne is positively cool by comparison. 33C today and then bobbing around the 29-33C mark for the rest of the week. Although expect highs in the mid-30s in inland suburbs.

Very hot in regional town with Bendigo rising from 43C today to 44C on Wednesday and Wodonga getting to 45C midweek.

“On Wednesday a cool change will drop temperatures a bit but the proper cool change starts to come in on Friday. But hot gusty winds with elevated fire danger will come ahead of the cool change,” said Mr Sharpe.

In NSW, that cooler weather isn’t due to come through until Sunday which will be the first day with a high below 30C this week.

For Adelaide temperatures will dip to 35C on Thursday, then 32C and into the 20s for the weekend. Melbourne will be in the low-30s for the end of the week and then the low-20s for the weekend with possible rain.

With the heat building, fire danger is set to rise. Widespread Very High fire danger is likely over the coming week. Check the fire danger rating daily for the area you live in or may be visiting. Report all unattended fires to triple zero. #NSWRFS pic.twitter.com/FRkxnAuP1i — NSW RFS (@NSWRFS) January 13, 2019

QUEENSLAND, THE TERRITORY, WA AND TASMANIA

Elsewhere, Brisbane will see identical sunny days at a far more manageable 32C all week with similar conditions up the coast to Cairns, but with the odd shower.

Darwin is 32C with the chance of storms for most of the week. Perth will be sunny and stay around 30C but the mercury could shoot up to 36C or even 38C on the weekend.

Heading down to Tasmania a summery 25C on Monday in Hobart will rise to 29C on Tuesday. In Launceston expect 34C midweek. Cooler than the mainland for sure, but still unusually high this far south.

— with AAP.