Temperature spike sparks fire bans, shuts schools

A total fire ban has been declared for the NSW south coast and Greater Sydney region on Tuesday, when temperatures are forecast to reach 33C.

There are 61 fires burning across the state at 9am with 13 yet to be contained.

Angus Hines from the Bureau of Meteorology says Wednesday is expected to be hotter reaching 34C with parts of South Australia and Queensland to also feel the heat.

"Most of Australia is sitting at moderate or high fire (danger) for the next few days," he said.

"The south coast of NSW has a small area of extreme fire danger there, overlapping with the heatwave conditions on Tuesday."

It's the first total fire ban for Greater Sydney since late November 2020, NSW Rural Fire Service spokesman Ben Shepherd said.

Conditions in Queensland are expected to ease on Tuesday and Wednesday with only smoke alerts issued, Fire and Emergency Service deputy commissioner Joanne Greenfield said.

By Thursday the high to extreme fire dangers will be more widespread, including a large part of the Channel Country in Queensland.

Southeast Queensland can expect a cooler change to roll through on Friday, according to the BOM.

Heatwave warnings are in place for Sydney, parts of the Hunter and the south coast.

More than 3000 kids have been told to remain at home after the NSW Education Department listed 21 schools that will be closed on the south coast on Tuesday.

"Schools with elevated bushfire risk will be temporarily closed ... due to extreme fire danger ratings being declared," a statement read.

The fire ban and school closures apply across areas including the Bega Valley and Eurobodalla Shire.

Sydney and the Hunter region will see the worst of the conditions on Wednesday before temperatures ease on Thursday, RFS Commissioner Rob Rogers said.

"It's the worst risk we've faced since the Black Summer fires of 2019," he said.

"We're in for a tough couple of days and we need the community to be very vigilant."

The heat is expected to shift north later in the week into parts of Queensland, the Northern Territory and Western Australia, driving maximums to 40C.

A severe wind warning is in place for Tuesday in parts of the NSW Snowy Mountains and south west slopes, with winds expected to become more damaging and widespread across the state on Wednesday ahead of a cold front.

Mr Hines said the winds have put emergency services on alert.

"On Wednesday we're going to see some warm windy weather around Sydney and the Hunter, with extreme fire danger forecast in those regions."

Fire crews have been busy in the NSW Hunter and southeastern parts of Queensland, with a fire burning at Beerwah on the Sunshine Coast shifting between advice and watch-and-act for days.

Australian Associated Press