Sydney has experienced its hottest weather in nearly 80 years as temperatures hit a blistering 47.3°C (117F) in the Australian city on Sunday.
"We can expect both high maximum temperatures and high minimum temperatures, so it will be harder to cool down", he said.
Monday's forecasted winds and rainfall won't penetrate too far west, with Penrith and Richmond still expected to reach up to 40C while parts of the Hunter Region brace for temperatures up to 43C, he said.
According to the NSW Bureau of Meteorology (BoM), Penrith beat Sydney's previous record of 47 degrees, which was recorded in Richmond on February 11, 2017, at 3.25pm today.
The greater Sydney area was given a severe fire danger rating. Residents of Carrum Downs on the southern outskirts of Melbourne were evacuated from their homes on Saturday as a bushfire edged closer, local media reported.
"One of the common things we see people do is throw cigarette butts down", said Rob Rogers, deputy commissioner of the New South Wales Rural Fire Service. They've also informed residents that if they are considering leaving their homes, they should do so earlier rather than later.
NSW Health urged people to drink plenty of water but say they are prepared for a rise in deaths and emergencies during the heatwave.
EPA FLOCK Beaches were packed today in Sydney Australia
Sydney is forecast to have poor air quality on Sunday which can especially affect people with asthma and chronic obstructive pulmonary disease.
The CFS battled more than 40 fires across the state on Saturday - 19 in rural areas.
Dr Scalley also warned of the dangers of a heatwave which put strain on the body, can cause dehydration, heat exhaustion and heat stroke.
CEO of Surf Life Saving NSW, Steve Peace, warned members of the public to be extremely careful on the state's beaches.
"Cars become a furnace very, very quickly in this type of heat", she said.
The two bystanders then rushed to the man's aid and brought him ashore, where he was taken to hospital in a stable condition.
A 48-year-old is fighting for his life after he was found face down in the water at Sandon Point Beach on Saturday.
Billabong agrees to a $380 million takeover by Oaktree Capital
A Billabong spokesperson confirmed there would be no job cuts in the near-future as a result of this deal. Once that happens, Billabong will become a private company and be taken off the Australian share market.