Weather changes overnight will put more communities in the line of bushfire, the state's fire authorities says.
Winds gusting to 100kmh whipped up the two largest blazes that had started on Thursday; at Forcett, near Dunalley in the state's south, and Lake Repulse near Mt Field National Park northwest of Hobart.
A Tasmania Fire Service incident management team spokeswoman said a predicted weather change overnight will affect the Lawrenny and Hamilton communities to the east of the Derwent River.
The communities are expected to be directly impacted by about 6am today (local time) by embers, spotfires and potentially a fire front.
"Communities have been asked to enact their bushfire plans now," the spokeswoman said.
"If their plan was to leave or if they don't have a plan, that they need to leave and go to a friend's or relative's place or the community fire refuge."
Meanwhile winds are pushing the other large bushfire at Forcett, in an easterly direction, impacting the communities of Bream Creek, Copping and Boomer Bay.
"They've been asked to go to their nearby safer place which has been identified as the Falls festival site at Marion Bay, only if the path is clear, though," the spokeswoman said.
"It's severely impacted on Dunalley already.
"You can imagine that the same thing could possibly happen in other communities. We don't want to underestimate this fire."
Meanwhile Tasmanian police are investigating reports of a death in the Forcett fire, that also destroyed homes, and damaged a school and an RSL club.
Police say up to 65 buildings could have been damaged or destroyed in the small community of Dunalley, 55 kilometres southeast of Hobart.
People had also been told to leave the beachside town of Dodges Ferry.
