Drivers in NSW are being urged to take care as a record-breaking heatwave reaches such extremes that roads in some parts of the state are starting to melt.

Towns in the state’s upper west, including White Cliffs, Borrona Downs and Tibooburra Airport, saw temperatures again exceed 45 degrees on Friday, as more records threaten to break.

Ivanhoe and Menindee in the far west are forecast to reach as high on 48 on Friday. Meanwhile it was reported bitumen on the Oxley Highway near Wauchope started to melt about midday on Thursday.

The extreme temperatures are reflected in the latest heatmap where dark shades of black are now visible, showing areas that are above 46 degrees.

View photos The temperatures in some parts of the country are so high, the heat maps are turning shades of black. Image: Windy TV More

View photos Parts of the Oxley Highway near Wauchope have started to melt. Image: Facebook/Rene Snyman More

Sydney’s CBD is expected to reach a more bearable 34, but in the city’s west, suburbs including Penrith are tipped to climb past 40 degrees.

Broken Hill and Canberra are slated for their fourth day in a row of days above 45 and 40 respectively – neither of which has happened since records began in those regions.

Spare a thought for those at the Tamworth Music Festival, which starts on Friday, when fans will swelter through temperatures in the low 40s.

“If you’re camping, it could be quite unpleasant in the tent,” the Bureau of Meteorology’s Anita Pyne said.

Health authorities are urging people to take extra care and keep hydrated during the heat, especially the elderly and children.

Australia has a new heat record! Overnight, #Noona in the #NSW west recorded a 35.9C MINIMUM temperature. It's the latest in a series of broken records in this #heatwave

Heatwaves are dangerous – stay hydrated & look out for others! #beattheheat

Forecast: https://t.co/nTTbM3WZEP — Bureau of Meteorology, New South Wales (@BOM_NSW) January 18, 2019





View photos Adelaide beachgoers launch themselves from a jetty to escape the heat. Image: AAP More

View photos Temperatures have reached an 80-year high in some areas. Source: AAP More

Those with heart conditions are also being warned about the dangers during the heatwave, as dehydration can reduce the amount of blood around the body.

“For people with heart disease and those who are at high risk of a heart attack, these changes can overwhelm the heart and could even result in a heart attack,” Heart Foundation NSW chief executive Kerry Doyle said in a statement.

But some relief is on the cards for southern and central NSW, as a cooler change pushes through on Friday night and into Saturday morning.

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