UPDATE: TASMANIAN firefighters have issued a watch and act alert as a bushfire between Forcett and the Tasman Peninsula grows in strength.

Authorities are trying to contain the fire before the next forecast high fire danger day on Thursday.

The Tasmanian Fire Service issued the watch and act message today for communities near the blaze, noting there had been an increase in activity on the blaze boundary in the Kellevie, Bream Creek and Marion Bay areas.

Residents south of Eaglehawk Neck along Blow Hole Road to Doo Town were also advised to remain vigilant but there was no immediate threat to those communities.

TFS senior station officer Phil Douglas said the fire had grown to cover 23,600 hectares, and fire crews were back burning to contain the blaze.

"It's not growing at a rapid rate at the moment but it is increasing every day," he told AAP.

"There are areas that are very difficult to access so the only way we can stop this fire is to actually burn those fuels out before the main fire gets there."

Mr Douglas said the combination of temperatures of around 26C to 28C today combined with strengthening west to southwesterly winds meant the fire could reach some towns.

"It does have the potential to possibly impact on some communities if it gets away," he said.

"So what we're asking people to do is really just keep an eye on what's going on so that's why it remains a watch and act (message)."

He said the next high fire danger day in Tasmania was likely to be on Thursday, with temperatures of around 32 degrees expected.

Meanwhile, the state's bushfire season is still weeks away from its most dangerous period, authorities have warned.

TFS chief officer Mike Brown said historical records show the island state's bushfire peak is in February.

"One thing that I'm quite fearful of is that we are only very early into our fire season," he said yesterday.

"I'm also concerned that over the continent of Australia we've got an extremely large mass of very hot air.

"If we have the pressure systems lined up and we get the strong winds again we could very easily have extreme or worse fire conditions again."

Mr Brown said the flattening of near whole villages such as Dunalley showed coastal areas could not afford to be complacent.

"We've got to realise that, in particular, southeast Australia is one of the most fire prone places in the world," he said.

Tasmania's three major newspapers will carry the TFS's bushfire plan guide this weekend as authorities brace for the rest of the summer.

Police say they have finished searching 1040 damaged properties hit by the Tasman Peninsula blaze and have recovered no bodies.

They say they've received no missing person reports and there are no serious concerns for any person's whereabouts.

The near miraculous lack of fatalities has been a result of lessons heeded after Victoria's Black Saturday fires in 2009, Mr Brown said.

"The fact that so far we've had no loss of life does distinguish these fires from so many of the tragedies that Australia's experienced in the past.

"The protection of life in the face of such catastrophic conditions is a very significant achievement.

"It's a good outcome but at this point in time we really must use this as a learning opportunity for the future."

A Forestry Tasmania worker suffered a suspected broken arm and dislocated shoulder fighting a blaze in the Derwent Valley northwest of Hobart.

"The area he was working in is very steep and broken ground," FT spokesman Tony Blanks said.

"I imagine he lost his footing and has just fallen and landed awkwardly."

He has been evacuated from the area and taken for medical treatment.