Millions of Queenslanders are being told to prepare amid warnings of the first cyclone to cross the state’s southern coast in half a century.

Tropical Cyclone Alfred will make landfall in South East Queensland by Thursday night or early Friday morning as a Category 2 system.

BOM Senior Meteorologist Dean Narramore told Sofie Formica on 4BC Afternoons, "It's currently a Category 2 and will cross as a Category 2, not Category 3 at this stage."

"Look, there's a tiny window that it might intensify, it's still a low chance. But if we go Category 2 or low-end Category 3, there's really not much difference." Mr Narramore continued. 

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