It was one of 45 fires that were burning around the state on the first day of summer, including several in which residents have been placed on alert:

 In the north-east, residents of Musselroe Bay were put on alert after a fire broke out near the town.

  Homes were at risk at Glenlusk in the state's South after a bushfire there broke containment lines - it was brought back under control in the afternoon.

 Three other major fires have been burning in the South - at Geeveston, Glen Huon and Forcett.

Near Poatina, fire crews from Hillwood, Meander, George Town, Bishopsbourne, Cressy and Karoola worked the night shift and will be replaced this morning by the crews who covered the blaze yesterday.

The fire is burning between Great Lake to the north of Arthurs Lake and to the edge of the Great Western Tiers.

During the day more than 60 firefighters, 10 vehicles and two helicopters from both Forestry Tasmania and the SES fought the blaze in hot, windy conditions.

Incident controller Chris Arthur said the fire had grown from covering an area of about 2000 hectares yesterday morning, to almost 8000 hectares by last night.

The only reported property damage was to Transend powerlines.

``The fire has been burning around and underneath the transmission lines, and we've been in consultation with Transend for most of the day,'' Mr Arthur said. 

``The transmission line has been slowed down and shutdown a couple of times.''

He said although the fire was expected to calm down overnight, the forecast for today was only marginally better and temperatures would remain high with windy conditions. 

Mr Arthur said people should stay away from the area.

A Parks and Wildlife Service spokesman said the cause of the fire was unknown but investigations would begin once the area was safe.

Updates can be found at the Tasmania Fire Service website - www.tfs.gov.au - or listen for emergency updates on ABC local radio.