Some roads outside Sydney were closed and authorities asked people to delay travel, at the start of what is normally a busy Christmas holiday period, warning of the unpredictability of the fires as winds of up to 70 kph (44 mph) were set to fan the flames.
“Catastrophic fire conditions are as bad as it gets,” NSW Rural Fire Services Commissioner Shane Fitzsimmons told journalists.
“They are the very worst of conditions. Given we have a landscape with so much active fire burning, you have a recipe for very serious concern and a very dangerous day.”
Greater Sydney and two surrounding areas were rated as catastrophic for Saturday, and other areas were at extreme or very-high fire danger ratings.
Close to 10,000 emergency personnel would be working across NSW on Saturday. The state’s Minister for Police and Emergency Services David Elliott described it as probably the largest emergency deployment ever seen in NSW.