Homes and livestock have been destroyed in NSW during catastrophic bushfire conditions on the weekend, but no lives were lost, authorities say.
More than 2500 firefighters worked during the weekend to fight more than 120 bushfires across the state, with areas in the central western part of NSW the worst hit.
"Some volunteers fighting to save other people's properties actually lost their own," Premier Gladys Berejiklian told reporters at RFS headquarters in Sydney when thanking all those who'd fought the blazes.
Two firefighters required hospital treatment, Rural Fire Service commissioner Shane Fitzsimmons said on Monday.
One firefighter is in Tamworth hospital with burns to the hands and face, while another is in Mudgee hospital with a serious laceration to the hand.
While firefighters dealt with the catastrophic conditions, Mr Fitzsimmons also praised the collective effort of RFS teams, community services, media and the community that no lives were lost.
"More than 1.5 million warnings were sent by telephone messaging to different parts of the community over the weekend," Mr Fitzsimmons said.
Fire expert teams are heading to central west NSW to assess the sheer scale of loss from the weekend's blazes, as more than 80 bushfires continue to burn across the state on Monday.
"We know that there are going to be homes lost. We know there are plenty of other buildings that have been destroyed," he said.
Livestock, machinery and community infrastructure such as churches and town halls have also been destroyed, he said.
The Sir Ivan fire, east of Dunedoo, has burned through almost 50,000 hectares with an active fire edge of about 200km, Mr Fitzsimmons said.
The nearby village of Uarbry has suffered significant damage, he said.
Cooler temperatures on Monday, after Sunday's catastrophic conditions, will help crews gain an upper hand but the heat is forecast to return by the end of the week.
Although conditions are easing, people in the area should remain vigilant and prepare to implement their bushfire survival plan.
A southerly change on Monday is pushing the fire towards Leadville and Coolah, according to the RFS.
The Kains Flat fire northeast of Mudgee has burnt through 5000 hectares.
Residents around Wollar and Cumbo should remain vigilant and prepared to implement their bushfire survival plan, according to the RFS.
"We need them to help bring these fires under control," Mr Fitzsimmons said.
Critical backburning and patrol work will be undertaken in the coming days.
The fire danger would remain very high on Monday in the Greater Hunter and surrounding fire areas, Bureau of Meteorology senior forecaster Neil Fraser told AAP.
Three people, including a teenage boy, have been charged with lighting fires over the past three days at Mango Creek on the Central Coast, at Orange in the central west, and at Nabiac on the north coast.
