Temperatures are warm – between 25 and 28 degrees in the city and pushing 34 in parts of the west – but seem well off the 39 degrees predicted by the Bureau of Meteorology. Are we in for a cooler day than expected?

Not according to forecaster Angus Hines, who still expects parts of the city to brush 40 degrees.

“It’s only about 25 degrees on the New South Wales coast. That’s because that strong wind has not yet kicked in,” he said in a weather update.

“But a little bit later on, about lunchtime, anticipate this very hot wind to start to race across eastern parts of New South Wales. That wind is packing a lot of heat.”

Those hot winds will propel the higher temperatures and worsen fire danger from the Hunter to the Shoalhaven.

“In conditions like this, if any fires do ignite, or if there are any ongoing bush fires through these areas, they can spread extremely quickly and be very hard for fire crews to control and contain,” Hines said.

He said the temperatures sizzling across NSW were more typical of a summer heatwave than spring.