Canberra, Jan 18 (IANS): Australia's heat wave dragged into its sixth day on Friday, with roads melting and heat records broken.

The six days from January 12 to 17 were all within Australia's 10 hottest days on record, the Australian Bureau of Meteorology said.

At Wauchope, 373 km north of Sydney, bitumen was reported melting on the main highway, causing road workers to spray water to cool the surface so that it would not stick to car tyres, according to the local Argus newspaper.

Temperatures at some regional sites in New South Wales (NSW) clicked over 46 degrees Celsius on Friday, with one regional town breaking the state record for the highest-ever overnight temperature, ABC News reported.

Heat records were broken across eastern Australia also as temperatures soared in the high 40s.

Australia's highest night-time heat record was smashed on Thursday at Noona, 800 km west of Sydney, where the lowest overnight temperature was 35.9 degrees Celsius.

Records across South Australia, New South Wales and Victoria over the past week include 48.9 Celsius in Port Augusta, 47.8 Celsius in Andamooka and 46.4 Celsius in Griffith.

It is the second heat wave to hit Australia in less than a month. Just over two weeks ago, post-Christmas temperatures led to extreme or severe fire warnings across at least three states and intensified severe droughts across the country.