The Sydney metropolitan area faces a fire threat right at its door this summer and residents can't afford to be complacent, authorities warn.

NSW has already faced more than 2500 grass and bushfires this year with more than a thousand of those occurring within the last month.

At the official launch of the state's bushfire season on Monday, NSW Rural Fire Service Commissioner Shane Fitzsimmons said that weather forecasts had been "dramatically revised" and indicated a tough season ahead.

"We've gone from an 85 per cent probability of above average rainfall down to about 35 per cent in some parts of NSW," he told reporters.

He said firefighters were well prepared but community complacency, especially on Sydney's fringes, had been a problem.

"More than 70 per cent of people acknowledge and understand they live in an at-risk area but less than a third of them actually have a plan about what they'll do ... in the event they're impacted by fire," Commissioner Fitzsimmons said.

"She'll be right mate just isn't good enough. You need to take action now."

NSW Emergency Services Minister Michael Gallacher said police were right behind firefighters to catch any firebugs and added the community took a dim view of such "fools".

"There is nothing more soul destroying (for a community) when they find out a fire that has engulfed their streets, their suburbs, their homes has been lit intentionally by some fool."

On Monday 55 fires were burning across the state including 24 that were not contained.

Commissioner Fitzsimmons said NSW could face more total fire bans on Tuesday if cloud cover was low.