A severe cyclone expected to hit Queensland on Thursday is likely to rival, and on some measures, dwarf Cyclone Larry, which devastated parts of north Queensland.
The Bureau of Meteorology says Cyclone Yasi will be a severe category three or four cyclone when it crosses the Queensland coast, likely early on Thursday morning.
Bureau senior forecaster Ann Farrell said the latest modelling suggested Yasi would make landfall somewhere between Innisfail, in the north, and Proserpine, in the south.
If it hits as a category three, wind gusts up to 200km/h can be expected, and 250km/h if it builds to a four, as Cyclone Larry was when it devastated Innisfail and surrounding communities in March 2006.
It's currently off Vanuatu, about 1975km east, northeast of Townsville, and moving westward at about 30km/h.
"At this stage we're expecting it to continue moving towards the Queensland coast and intensify ... and it's likely to reach the coast early on Thursday morning," Ms Farrell told AAP on Monday.
"By that stage we will be looking at a severe tropical cyclone so certainly at least a (category) three, and a category four we wouldn't be ruling that out by any means."
She said the last cyclone of that magnitude to hit Queensland was category four Cyclone Larry.
Larry left a trail of destruction including damage to 10,000 homes and a repair bill of more than a billion dollars.
Ms Farrell said there were many measures on which to judge cyclones, including wind strength and the physical size of the storm. In terms of wind strength, Yasi had the potential to rival Larry, but it was of a far greater physical size.
"One measure is how far do the gales extend from the central eye. In this case, Yasi is certainly a bigger storm," she said.
She said forecasts for Yasi would be refined as it approached, but all the modelling showed it was on course to hit the coast.
She said Yasi was a fairly fast moving system, meaning it was unlikely, on current information, to stay in the same location and dump vast amounts of rain on an already flood-devastated state.
She said the other factor to consider was the storm surge that would likely accompany the cyclone.
"The more intense the system, the greater the concern about storm surges," Ms Farrell said.
"Certainly that is a distinct threat with this system. "How far up above the normal high water mark it reaches will depend on the timing and what the tide is. Whether it is high tide or low tide will make a difference."
