Fire activity has increased from Ulladulla to Kangaroo Valley, with forecast heat and wind taking effect this afternoon.
The increased activity is mostly along the eastern edge of the fire, RFS public liason officer Angela Daly said.
"It's starting to put up some more smoke, and we're getting more 000 calls," she said.
"Ground and aviation crews have been tasked to those as they come in.
"None of them have taken a big run as yet, but the situation could deteriorate from here."
Ms Daly urged anyone who saw an unattended fire to call 000.
She said residents must stay aware of changing conditions, and be ready to put their fire plan into action if they have not already done so.
"Waiting for a knock on the door or a text message is not a plan," she said.
"Conditions may deteriorate so quickly it is not possible to send an emergency message."
Residents are encouraged to follow the Live Traffic and Fires near me websites, as well as listen to local ABC Radio.