Parts of New South Wales will hit 47 degrees Celsius today as a heatwave sweeps across the country.

Hay, a town in the western Riverina region of south western New South Wales, will be hit the blistering temperature of 47 degrees, while other parts of the state suffer similarly stifling heat.

The far west of the state in areas such as Wentworth, Menindee and Broken Hill temperatures will also reach 45-46 degrees.

Meanwhile, it looks like Sydney will max out 30 degrees.

It follows heatwave warnings from the Bureau of Meteorology on Monday.

Hot air, which has been sitting over the Pilbara mining country in Western Australia for weeks, has now begun to move east and will see scorching temperatures reach most of continental Australia and large parts of Tasmania over the course of the week.

The worst is likely to come towards the end of the week, as a second wave hot air moves towards the eastern states, the most densely populated areas of the country.

While Sydney was expected to exceed 40C on Tuesday, BOM forecaster Anita Pine says the sea breeze is cooling conditions, particularly towards the evening.

Despite that she said overnight temperatures will still be “very uncomfortable” and it will be difficult to sleep if you don’t have air-conditioning.

She said the Riverina remains the “epicentre of the worst heat”.

While current conditions in the area haven’t set any records, the last time Hay experienced five or more days of temperatures above 43 degrees was the summer of 2014 — a record which could be broken this week.

Pine also stressed the dangers of heatwaves, which “cause of most deaths of any natural weather event” and can put the elderly and sick at risk.

The Bureau of Meteorology will hold a media conference at 1pm AEDT.

*Additional reporting by Paul Colgan.

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