Strong winds fanned the flames around Ulladulla early on Wednesday, with some residents evacuated while others were told to seek shelter as it was too late to leave.

About an hour's drive north, emergency services have battled to control another blaze threatening property at North Nowra, forcing the closure of the Princes Highway in both directions. Train services on the South Coast Line were also suspended from Kiama to Bomaderry.

And further south, towards Bega, an emergency warning was issued for a 300-hectare fire burning out of control at Bemboka.

These major south coast bushfires are the worst of dozens of early-season blazes that firefighters are battling across the state under severe conditions, with a total fire ban declared for Sydney, the Illawarra and Hunter regions until midnight on Wednesday.

It's the earliest declaration of a total fire ban in the regions in almost a decade, the NSW Rural Fire Service tweeted on Wednesday afternoon.

More than 800 firefighters were battling more than 80 fires across the state, with 50 of those not contained.

With conditions easing on Wednesday evening, the RFS tweeted around 9pm that all fires in NSW were downgraded to Watch and Act alert level.

But the fires around Ulladulla and Bemboka continue to burn out of control – and are expected to do so for several days due to the lack of easy containment lines.

NSW RFS Inspector Ben Shepherd said the Ulladulla region fire had "whipped up unbelievably quick" on Wednesday morning under the strong gusts.

"The fire is moving quickly under some very strong north-westerly winds towards the Burrill Lake area," he said. "It's very erratic and it's very dangerous."

By late afternoon, attention turned to Bemboka where conditions had become "very dangerous", the RFS tweeted.

"The fire is burning in difficult terrain, which is making conditions dangerous for firefighters and residents. Seek shelter if the fire impacts."

Any easing of conditions is likely to be short-lived, with temperatures and wind whipping up again on Saturday.

"We are concerned about a return to these gusty conditions on Saturday," RFS Deputy Commissioner Rob Rogers said.

With the entire state drought-declared and unseasonably warm winter temperatures, Mr Rogers said firefighters were expecting this season to be bad.

"We do get fires in August, but the big difference is 100 per cent of the state is drought declared," he said. "It’s only been three months since the last fire we had in Holsworthy in April.

"Hopefully this isn’t going to be a sign of things to come."

Milton resident Jodi Smith said the fire was a "small glow on the mountain" when she went to work at 4.30am on Wednesday.

She had to leave after the wind picked up and she was overcome by smoke on the property.

"I have lived here for 45 years ... but I haven’t seen anything like this," she said.

Nearby resident Barry Matthews said "absolutely howling" winds woke him about 6am.

"It had been burning for a few days, but we weren’t concerned at all," he said.

He watched the fire as he ate his breakfast before he was evacuated about 9am.

The RFS has urged property owners to think twice before burning off on Wednesday, as temperatures rise to the mid-20s.

Fire crews had already been on high alert with warm and windy weather forecast across the state.

The driest start to a year in NSW since 1965 has set the state up not only for a worsening drought but elevated the risk of bushfires.

Earlier this week, the Bureau of Meteorology warned of higher fire risks by Wednesday as rising temperatures and expected strengthening winds combined with the very dry conditions across the state.

Parts of the north-east have already had their official fire season brought forward a month to August 1, while the government is understood to be considering similar moves for other at-risk parts of NSW.

Even without an early declaration of the fire season – which brings restrictions on burning-off activities – authorities are understood to have been preparing to shift assets to regions that are considered to have especially high fire risks this spring.

Countering the ability to bolster resources is the deployment of about 200 firefighters to North America at the start of August, many of them from NSW.

That contingent is helping to co-ordinate responses to huge blazes that continue to burn in California and other US states.

The early-season bushfires are also likely to stretch the aerial resources of NSW and other states in Australia.

Most of the large firefighting aircraft don't typically arrive in Australia until after September, and demand for their services is likely to remain high in Europe and North America amid record summer heat in many regions.

The RFS says the state has access to many aircraft but those planes and helicopters typically have less fire suppressant capability than the leased jets and other aircraft brought in ahead of the summer fire peak.

NSW Emergency Services Minister Troy Grant said the fires are a wake-up call for residents in fire-prone areas.

"The current situation down south is a reminder to all residents across the state that could be affected by bush fires to take the time to discuss with your family what you will all do and where you will go in the event of a bush or grass fire," he said.

with Emily Barton, Milton-Ulladulla Times