Nation-wide weather, fire warnings amid heatwave

A heatwave has prompted a host of weather and fire warnings across Australia spanning Tuesday to Friday as the nation prepares to swelter.

NEW SOUTH WALES

* Extreme heatwave warning for the Illawarra, South Coast, Southern Tablelands, Snowy Mountains, South West Slopes and Riverina with the worst expected on Friday

* Sydney expected to hit 40C on Saturday

* Prolonged heat for southern central and western areas this week, with maximum temperatures in the high 30s to mid-40s across inland regions

* Heat to peak later this week, before easing from the south next week

VICTORIA

* Extreme heatwave warning for the Northern Country, northeast, East Gippsland and west and south Gippsland, with severe heat in areas including the state's centre and southwest

* In the north, maximum temperatures in the low-to-mid 40s. Melbourne set to reach 42C on Wednesday and 40C on Friday

* Severe to extreme heatwave conditions forecast to ease from the southwest over the weekend

* Extreme fire danger on Wednesday for the central, southwest and Wimmera areas

WESTERN AUSTRALIA

* Severe heatwave warning for the Pilbara, Gascoyne, Goldfields and the south interior, with heat expected to contract northward over the second half of the week.

* Maximum temperatures in the low-to-mid 40s, reaching high 40s in parts of the northwest

* Extreme fire danger on Wednesday for the Ashburton Coast and Exmouth Gulf Coast

SOUTH AUSTRALIA

* Severe heatwave warning for much of the state including Adelaide, with the capital to reach 42C on Wednesday

* Maximum temperatures in the high 30s to mid 40s, dropping to the low-to-mid 20s in the south over the weekend

* Extreme fire danger forecast on Wednesday for 12 districts including Kangaroo Island and the Riverland

ACT

* Prolonged heat this week, with Canberra to hit the high 30s before cooling off Sunday

TASMANIA

* Extreme heatwave warning for the Furneaux Islands, with a severe warning stretching across much of the state's centre, north and northeast

* Maximum temperatures in mid 20s to low 30s on Wednesday, with Hobart hitting 28C

NORTHERN TERRITORY

* Severe heatwave warning for Simpson and Lasseter in the territory's south, with maximum temperatures in the low-to-mid 40s

QUEENSLAND

* No heat warnings with the temperature in Brisbane staying around 30C