Homes on the NSW south coast are under threat from two out-of-control bushfires being whipped up by increasingly strong winds.

Emergency warnings were issued to residents at Mount Kingiman, south of Ulladulla, and in North Nowra on Wednesday morning, with some told it was too late to leave.

There are reports buildings have already been damaged by the fires, but the NSW Rural Fire Service is yet to confirm whether they are homes, sheds or other structures.

Winds from the north-west were fanning the blazes, and conditions were expected to get worse in the afternoon, with gusts of up to 110km/h predicted.

EMERGENCY WARNING – Croobyar Rd fire (Shoalhaven LGA) – Fire burning in Woodstock area, west of Burrill Lake. Updates at https://t.co/3QyPI84ofT #nswrfs #nswfires pic.twitter.com/dN6RYMDThP

— NSW RFS (@NSWRFS) August 14, 2018

Fire crews were on the scene to protect properties between West Cambewarra Road and the Princes Highway near Bomaderry, where the fire was burning close to homes.

“It’s right on them now,” NSW Rural Fire Service Deputy Commissioner Rob Rogers told the ABC.

“It’s impacting on homes in North Nowra as we speak. Our advice to people is to shelter in place.”

Further south, residents in Woodstock were also being told it was too late to leave as a 100-hectare bushfire moved towards Burrill Lake.

Spot fires were popping up ahead of the main fire front, sparking fears homes in Kings Point and southern Ulladulla could be at risk.

“Our concern is now, given these wind strengths, that we could actually start to see embers move onto the eastern side of Burrill Lake,” NSW RFS Inspector Ben Shepherd said.

“If the embers do take hold … they’re going to escalate very, very quickly under these extraordinary strong winds.”

An evacuation centre has been set up at the Ulladulla Civic Centre.

At least 40 crews are on the ground, with a further 20 on the way.

They are being helped by four water bomber helicopters but the fierce winds are making their work difficult.

There's currently 830 firefighters in the field, dealing with more than 70 bush and grass fires across NSW. Total fire bans are in place in Sydney, Hunter and Illawarra due to worsening conditions. #nswrfs #nswfires

— NSW RFS (@NSWRFS) August 15, 2018

Crews were also battling a fire on the Bells Line of Road near the Blue Mountains, with a “watch and act” alert issued for the Bilpin area.

The RFS said the fire might impact on properties in the next few hours.

A total fire ban has been declared for the Sydney, Illawarra and Hunter regions until midnight Wednesday as conditions deteriorate.

SES Illawarra region controller Greg Murphy told ABC radio the strong winds had torn off roofs and damaged trees, with crews already out and responding to calls for help.

About 2500 properties were without power in the Illawarra and Shoalhaven regions due to the winds.

Firefighters were gaining an upper hand on two other fires, one in Jerrara, west of Kiama, and another in Yatte Yattah.

A grass fire was also burning out of control in Jerrara, west of Kiama.

The RFS said the fire was burning “close to properties” but crews were on scene to try protect them.

EMERGENCY WARNING Croobyar Rd (Shoalhaven LGA) – Fire continuing to burn in the vicinity of Woodstock Rd W of Burrill Lake, with spotting occurring ahead of the fire front. Residents in Woodstock are advised to seek shelter as the fire approaches #nswrfs #nswfires pic.twitter.com/AMMD1ji5kS

— NSW RFS (@NSWRFS) August 14, 2018

Some 48 incidents were reported across the state between Friday and Sunday, 10 more than the previous weekend.

Commissioner Shane Fitzsimmons said the activity was concerning.

“Escaped fires pose a very real and potentially deadly threat to the public, especially if that escaped burn takes hold and fire authorities are not notified,” he said.

Landholders who fail to notify authorities and neighbours face fines of up to $5500 and/or 12 months in jail, while escaped fires can attract penalties of up to $110,000 and/or five years’ prison.

The bushfire danger period has already begun in parts of NSW, including Lismore, Richmond Valley, Armidale and Walcha.

It will start in other local government areas, such as Coffs Harbour and Kempsey, from Friday.

-with ABC, AAP