A search for a bushwalker missing for more than a week in icy conditions is being reviewed, with advice sought from survival experts.
Daryl Fong, 30, set off on a day hike in the Mt Field National Park area in Tasmania on October 11.
He last made contact with a friend about 3am the next day, saying he had been delayed and was planning to seek shelter overnight.
Tasmania Police on Monday said a review of the search was being conducted and advice obtained from specialist survival experts.
"Search personnel remain committed to finding Daryl but with the passing of time and the conditions in the area, serious concerns are held for his welfare," police said.
Waist-deep snow has fallen in the area. It has also been battered by strong winds which on Sunday stopped a vertical rescue team from searching and grounded a rescue helicopter.
Mr Fong's mobile phone has not been active and a personal locator beacon he is believed to have been carrying has not been activated.
His car, a white Subaru, was found in the Lake Dobson car park, where he left it when he started walking.
Martin Gotthard, a housemate of Mr Fong who reported him missing, has thanked search crews for their efforts.
"You have my sincere admiration for what you have done and are doing," he wrote on Facebook.
The temperature dropped to 2C in Mount Field at the weekend and is forecast to fall below zero on Tuesday.
The national park, one of Tasmania's oldest, is home to a diverse array of alpine vegetation, ranging from eucalypt forests to glaciated landscapes and cascading waterfalls.
Several bushwalkers have run into trouble in freezing weather in Tasmania in recent weeks, including a Chinese tourist who died at Cradle Mountain National Park in late September.
Peter Willoughby, 76, who got lost in bushland in the state's north on October 5 while trying to recover his bogged car, remains missing.
