Sydney's temperatures top 40 degrees as major heatwave grips the city

Temperatures topped 40 degrees in parts of Sydney today as a major heatwave gripped the city.

Suburbs in the city's west hit 40-degree temperatures as north-westerly winds spread from Central Australia.

The city exceeded the Bureau of Meteorology's expectations, reaching 38 degrees.

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NSW Ambulance Superintendent Steve Vaughan has warned people to beware of the heat.

"Everyone's susceptible to heat, whether you're young and fit, whether you're from a different social background or different cultural aspects," he said.

On the Mid North Coast, a bushfire at Bulahdelah burned through the night.

The blaze shut parts of the Pacific Highway, with residents being told to watch and act.

"Help our volunteer lifesavers out, swim between the flags. You know, know about risks on the beach—know how to spot and identify a rip current and be safe this summer," Adam Weir from Surf Life Saving Australia said.

Temperatures are expected to surge again tomorrow, with a forecast maximum of 36 degrees in the mid-afternoon for the city.

The BoM issued a heatwave warning yesterday that extends through to tomorrow.

"Severe heatwave conditions are expected to peak on Friday and Saturday before easing on Sunday as a cooler change extends across the State," the warning read.

The surging temperatures will not be confined to Sydney, with other affected regions including the Hunter, Illawarra, Central Tablelands, Southern Tablelands, and Snowy Mountains.

Total fire bans are in place for a number of western and southern districts including the Lower Central West Plains, and the Northern, Eastern, and Southern Riverina.

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The fire danger for much of the state, including Greater Sydney, the Hunter, and Illawarra, is expected to reach "Extreme" tomorrow.

People are urged to find ways to stay out of the heat today, including by drawing blinds or awnings early to keep the heat out of their home.

Fans and air-conditioners are also recommended.

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