Inland NSW is set to bear the brunt of another stint of steaming hot weather, with authorities particularly worried about the growing risk of grass fires.
Parts of Sydney - including the city - broke the 40C barrier for a second straight day on Sunday after swathes of western NSW, South Australia and northern Victoria baked through even higher Saturday temperatures approaching 45C.
The mercury on Sunday pushed past 40C in many Sydney suburbs, including Penrith, Canterbury, Bankstown and Holsworthy.
Observatory Hill in central Sydney also recorded its first-ever consecutive 40-degree November days.
Temperatures in Newcastle and across the Hunter were also well in excess of 40C, hitting 41.9C on Sunday at Cessnock Airport.
A gusty southerly arrived late on Sunday afternoon, quickly dropping temperatures by more than 10C in areas including Sydney.
The southerly change brought a brief respite from the warmer weather for most of NSW, but sweltering weather is forecast to return on Tuesday.
While coastal Sydney will experience temperatures in the low 30s on Tuesday, western Sydney and huge swathes of inland NSW will surpass 40C.
"Tuesday will be a repeat of the conditions we experienced yesterday," Bureau of Meteorology NSW Manager Agata Imielska told reporters on Monday.
"Very hot conditions, particularly for the inland, with a change also moving across quite late on Tuesday.
"For some of these locations, these temperatures were more what we would expect in a summer heatwave."
Southeast and southern Queensland are also set to experience elevated temperatures from Monday, with no relief until at least Thursday.
RFS crews battled more than 60 bush and grass fires across the state on Sunday, including blazes in the Blue Mountains and Kenthurst and a fire that damaged a home in the western Sydney suburb of Northmead.
NSW's Northern Slopes and North Western districts are on Monday subject to a total fire ban.
RFS Commissioner Rob Rogers on Monday said more than a dozen fires over the weekend were under investigation and may have been deliberately lit, including the Northmead fire.
He warned Tuesday could be a tough day for firefighters in inland NSW.
"Coastal areas should still have a bit of a coastal sea breeze effect but nonetheless it's going to be really hot," Mr Rogers told reporters.
"West of the ranges, it's going to be very hot, dry, strong northwesterly winds, very low humidity. The sort of conditions we saw on the weekend are certainly going to be replicated from the southern part of the state all the way to the northern border, mostly inland."
Mr Rogers also warned that rainfall across NSW in 2020 had caused significant grass growth, adding to the bushfire risk.
"There was no grass growing west of the ranges in the past few years because of the drought ... now there's significant growth, probably more growth than we've seen in a couple of decades. That concerns us as that starts to dry off," he said.
Last summer's bushfires destroyed 2476 homes and killed 26 people in NSW.
Meanwhile, Endeavour Energy said 2100 customers remained without power as at 11:30am on Monday after Sunday's strong winds.
Australian Associated Press