It was already 22 degrees in part of the city at 6am.
Some inland parts of the state are expected to exceed 40 degrees, particularly in the state’s north-west.
Meanwhile, a severe heatwave warning remains in place across New South Wales’ mid north coast.
Temperatures are expected to peak on Tuesday before milder conditions extend across the area on Thursday, reducing the heatwave conditions.
New South Wales residents are reminded heatwaves can be dangerous, especially for older people, babies and children, pregnant and breastfeeding women and people with medical conditions or are unwell.
People should seek shade, remaining in a cool indoor space and keep windows and blinds drawn.
Stay inside with the aircon on!
More information on staying safe during a heatwave can be found at the Bureau of Meteorology or the NSW Department of Health website.
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