Rural Fire Service commissioner Shane Fitzsimmons concedes it's a possibility."I don't think I've ever use the word mega-fire," he said."But the reality is that the modelling indicates that there's every likelihood that in the forecast weather conditions that these two fires, particularly up in the back end of the mountains, will merge at some point.''
The Lithgow fire could burn along the Bells Line of Road, threatening communities in Sydney's northwest from Kurrajong to Richmond. It may be that some communities "will be simply unsaveable", Mr Fitzsimmons said.