PREMIER Anna Bligh fronted a media conference at 10.30pm to report that 89,000 Queensland power users were now experiencing blackouts.
"More than half of those are in Townsville and Ingham area and the the CBD has now lost power," she said.
A number of evacuation centres would now be without electricity.
"Cyclone Yasi shows no signs of weakening," Ms Bligh said.
"People may need to be self-sufficient for a couple of days.
"It will depend on conditions, how quickly we can get helicopters up ... the army may be able to assist.
"I can't sugar-coat this for people. It's going to be a tough couple of hours and for many people it may be a tough couple of days."
The premier said a wave height that had been recorded at 18m off Townsville was incorrect.
It was recorded by a wave buoy in an area where waves do not usually break but waves were now breaking over the buoy, creating inaccurate readings.
However, strong storm surges would occur in Townsville, where the highest tide of the year had now been recorded.
"We are seeing the beginnings of the building of that storm surge that we indicated would build up over a three-hour period."
Asked whether Yasi's power had yet taken any electricity transmission towers offline, Ms Bligh said: "We are still two hours away from the kind of force that would lift a transmission tower.
"Then it will prevail for some three to four hours."
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