Scorching heatwave to smother Sydney as hot air mass moves across NSW

A scorching heatwave is set to blanket Sydney and much of the east coast as a hot air mass moves across the country.

The Bureau of Meteorology has issued a severe heatwave warning for metropolitan Sydney, the Hunter, Illawarra, Southern Tablelands and Snowy Mountains and an extreme warning for the south coast from today until Saturday.

The maximum temperature is forecast to sit around the high-20s to mid-30s, and will continue to rise as the week goes on.

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Today, temperatures of up to 30 degrees and strong winds will create uncomfortable conditions in Sydney.

The temperature will hit 34 degrees tomorrow and 36 degrees on Saturday, when some rainfall is expected in the late afternoon.

The entire state will be under a moderate to extreme fire warning from today until the end of the week.

Sydney, the South Coast and central and northern parts of NSW are under a high fire danger warning today and tomorrow.

The warning will elevate to extreme fire danger on Saturday when heatwave conditions peak before lowering back down on Sunday.

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The conditions are being caused by a hot air mass that built over Western Australia at the start of the week and has since moved east.

The system caused temperatures to reach 48 degrees in parts of central Australia, following an abnormally cold start to summer that saw snow fall in the mountains.

A cool change is expected to move across the east coast on Sunday and Monday.

Sydney will see a maximum temperature of 25 degrees with showers expected for most of the day on Sunday and 26 degrees and cloudy conditions on Monday.

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