"Over at least the next 24 to 48 hours,we've got more favourable conditions across NSW,"said RFS spokesman Ben Shepherd.
"What that's enabling us to do is get on the front foot,and we are conducting a number of back burns across all fire grounds before we see a return of windy weather."
He said they had made progress at a number of massive sites,notably the Gospers Mountain and Three Mile fires,which had been wreaking havoc in the Hawkesbury and Gosford,respectively.
"We have been able to curb those fires'easterly spreads,they've done some really good work up there and that will continue,"Mr Shepherd said.
"We are trying to get the fires under control but we're talking about huge areas - there's literally hundreds of kilometres along these containment lines."
On Thursday afternoon,there were 2600 firefighters battling 130 fires.