NSW Premier Gladys Berejiklian urged people to evacuate bushfire hotspots while they still had time.

“I’m pleased to say that we’ve never been as prepared as we are today for the onslaught we’re likely to face,” she told reporters today.

“All of the major road networks are still open, but we can’t guarantee that beyond the next few hours. So, there are still windows for people to get out.”

There are some 137 bushfires burning in NSW today, with around 60 uncontained.

More than 3000 firefighters are on the frontline, with 31 specialist strike teams in place across NSW.

NSW Rural Fire Service Commissioner Shane Fitzsimmons said temperatures would soar past 40C in southeastern NSW before a “volatile” southerly wind sweeps through in the afternoon.

“We’re going to have a long day dominated by hot temperatures, dry atmosphere and winds coming out of the ranges,” he told reporters.

“It will make for a very dangerous day and it will make for volatile fire grounds.”

Extreme fire danger is forecast for six fire districts in NSW’s southeast and the ACT, while severe conditions are forecast for Sydney, the Hunter and the central ranges.

Five “no go” zones have been established across broad sections of the south coast, parts of the alpine region and on fire-threatened parts of Sydney’s fringes.

Authorities are urging people there to head to cities, large towns, already- burnt areas or beaches if they havn’t already left.

Bureau of Meteorology spokesman Grahame Reader said conditions were shaping up as “very dangerous”.

“We have three main threats today – the fires themselves, the smoke, and the heatwave conditions,” he told reporters.

“Through southern and central NSW there is the potential for dry thunderstorms. The danger is they could start new ignitions.”

Temperatures are forecast to reach 45C inland and up to 44C on the coast. Sydney’s outskirts could hit 46C. A gusty southerly is forecast to reach the far south coast from mid-afternoon, reaching Sydney about midnight.

Hospitals in Batlow, Pambula and Tumut have been evacuated as well as healthcare facilities in Tumbarumba and Delegate.

The Regional Express airline suspended all NSW south coast services on this morning due to the extreme bushfire conditions.

Bega Valley Shire Council Mayor Kristy McBain said this morning she was “anxious” about the forecast.

“I’ll be managing the health and safety of my children and if we are required to leave we will go to an evacuation centre in Merimbula,” she said.

RFS spokesman Marty Webster says people are cutting it fine if they still haven’t left bushfire danger zones.

“There is still time to leave but please don’t leave it any longer. You need to be acting now.”

Liberal Bega MP Andrew Constance, who plans to defend his home on today, said the region could be “smashed”.

“We have got over 500,000 hectares ablaze. That’s a massive, massive fire front,” he told the ABC on today morning.

A statewide total fire ban will remain in place on today, as will a state of emergency, which is the third declared in as many months.

Eight people, including a firefighter, have died since Monday. Another man, seriously burnt in a bushfire in November, died in hospital on Sunday.

Meanwhile, the bushfire danger has eased on Kangaroo Island with warnings reduced to a watch and act but not before the fire had burnt through up to 100,000 hectares.