"It will be a tough week for firefighters because unfortunately what we really need is a meaningful rain right across this fire ground and right across other parts of NSW", he said.
The fire, which started at about 2.30pm on Saturday, has blackened more than 2400 hectares and continues to burn towards Barden Ridge.
On Sunday, more than 500 firefighters in nearly 100 fire trucks, along with 15 aircraft, battled the blaze throughout the day.
The blaze, which has been burning since Saturday, was downgraded from emergency to watch-and-act status overnight, but it has flared up again.
Firefighters worked through the night to backburn areas around Heathcote Road near Pleasure Point, as well as the Holsworthy military base.
The bushfire threatened homes in Sydney, with some locals being forced to evacuate their homes over the weekend, while others were told it was too risky to leave.
RFS spokesman Greg Allan said some properties had not escaped unscathed.
"It is absolutely miraculous that we have not lost any lives and virtually no property and this is because of the hard work and dedication and heroism of our fire services", the state's acting Emergency Services Minister Mark Speakman told reporters Monday.
By 5pm, some Menai residents were starting to relax.
Police are investigating whether the fire was deliberately lit. (9NEWS) More than 500 firefighters have worked to contain the blaze over the weekend.
New South Wales RFS said the blaze was "highly suspicious", with Commissioner Shane Fitzsimmons saying, "How dare anyone - if they are deliberately involved in lighting fires - endanger our firefighters and also [put] all these communities in harm's way".
While no buildings have been destroyed, homes are under imminent threat.
"Still quite a hard day ahead (on Monday)", Rogers told the Nine Network.
"I think we've got a long way to go before we're out of the woods".
The latest update from NSW RFS warned residents in Voyager Point, Pleasure Point, Sandy Point, Alfords Point, Barden Ridge, Illawong, Menai and Bangor to remain vigilant, as winds are expected to pick up throughout the day, which could increase the fire activity.
Fire investigators were still working to determine the cause of the fire, but Fitzsimmons said it was most likely deliberately lit.
The flames briefly shut a section of the T8 train line, while several roads remain closed.