Category 5 is considerable stronger than Katrina (Category 3) which devasted New Orleans in 2005.
They are expecting rainfall of 700 - 1000 mm during the storm!!!! Given that flash flooding can occur at 100mm or 10% of that, it is going to be very messy! They are also expecting winds of up to 300 Kilometres per hour.
All low lying areas are being evacuated, and hopefully people will get the heck out of there whilst they can, just been watching the news reports, and the window to evacuate is only the next 3 hours.
Poor old Queensland, first the flooding, now this....Our thoughts are with you guys!