Sustainable Timber Tasmania confirmed the south-east front of the fire had damaged assets, but the extent of the damage was not yet known.

“The fire has had some impact on Permanent Timber Production Zone land. An assessment of the impact hasn't been made and STT is focused on control efforts at this time,” an STT spokesperson said.

The fire stayed within containment lines overnight and crews are focusing their attention on the south-west corner to consolidate the area north of the Gordon River.

Gell River fire operations officer Mark Klop said clear weather conditions were needed to fly firefighters in by helicopter, given road access was non-existent.

“It is quite an exposed area when it comes to weather and can cloud in and make firefighting dangerous,” he said.

“We can try and contain the fire as best we can for this point of time, but it will take a good rain event to extinguish the fire.”

Thirty firefighters were on the ground on Monday with a further 30 providing operational assistance.

Related: TSF monitoring east coast, central midlands conditions

The fire has burnt up to the edge of Lake Rhona and to the top of Denison Range, burning in buttongrass and other vegetation.

Mr Klop said Sunday was a difficult day for firefighters, but conditions were expected to improve.

“Weather is really good for the operations we’re conducting today. Yesterday was heavy cloud and we struggled to get air operations happening so we couldn’t insert firefighters,” he said.

“The coming days are looking pretty good for putting firefighters in there, however we’re always vigilant about wind changes and if we need to evacuate firefighters from areas.”

The fire was caused by a lightning strike on December 27, but weather conditions caused it to spread on January 4 and head south-east towards Maydena.

Vica Bayley, of the Wilderness Society Tasmania, said questions needed to be asked about the initial response to the fire, including whether a decision was made to allow it to self-extinguish.

“There are two questions: How has the government responded to the review to increase its firefighting capacity? And operations-wise, what work did Parks and Wildlife and the TFS do initially?” he said.

“Recommendations from the 2016 bushfires were that you need to jump on these remote fires as soon as possible.

“When the BOM sees a weather event coming through, assets need to be on standby.

“There are reports that they were waiting for it to burn out.”

Related: Smoke blankets Hobart, flights diverted to Launceston as firefighters battle blaze

Mr Bayley said his criticism – along with criticism from unions and other environmentalists – was not aimed at those fighting the fires, but at operational decisions.

Tasmania Fire Service deputy chief officer Bruce Byatt said efforts were undertaken to extinguish the fire initially, but buttongrass could often obscure which areas were burning.

“There was a significant effort put in to controlling that fire by all agencies prior to that significant weather day. The fact that that day occurred is what provided that significant run on that fire,” he said.

The 2016 fires prompted a Senate Inquiry. Greater resources were among the recommendations.

Emergency Minister Michael Ferguson said “armchair critics” of the response were “un-Tasmanian”.

“Operationally, we always review our TFS and our Parks service will always review how fires were contained and managed,” he said.