DESTRUCTIVE winds with gusts of over 125km/h are occurring about the Whitsunday Islands, as Tropical Cyclone Debbie edges closer to the Queensland coastline.
The system was officially upgraded to a Category 4 at 8pm.
Queenslanders are being warned to brace for what the Premier described earlier as "a monster of a cyclone", with mass evacuations in place considered to be "the largest we've ever had to do".
The cyclone is expected to hit the mainland about 10am, with the very destructive core crossing the coast between Ayr and Cape Hillsborough, just north of Mackay, late on Tuesday morning.
It is currently tracking west south-west at 6km/h.
Sustained winds near the centre of 175km/h and wind gusts up to 250 km/h have been measured.
Areas from Lucinda to St Lawrence, including Townsville, Mackay, and the Whitsunday Islands, extending inland to Charters Towers, Mount Coolon, Moranbah, and Pentland, are in the warning zone.
People on the Whitsunday Islands are advised to seek shelter and remain inside.
Those living between Ayr and Mackay should complete preparations quickly and be prepared to shelter in a safe place.
Dangerous storm tides are forecast between Ayr and St Lawrence as the storm crosses the coast.
"The sea is likely to rise steadily up to a level well above the normal tide, with damaging waves and flooding of some low-lying areas close to the shoreline as the cyclone approaches the coast today," the bureau said.
Heavy rain and severe flash flooding is forecast for the central coast and Whitsunday district. This rain is likely to produce flooding over a broader area this week, with a Flood Watch in place for catchments between Rollingstone and Gladstone, extending inland to the Upper Flinders, Thomson and Barcoo catchments.
CYCLONE DEBBIE FROM SPACE
About 11pm Mackay police advised residents in the red or green zone to leave their address immediately.
The Mackay Cyclone Shelter at 30 Rosewood Drive, Rural View, was open for those with no other option for refuge.
According to Ergon Energy, 4103 homes are without power in the Airlie Beach region, due to "damage caused by cyclone activity".
Ergon said homes in Airlie Beach, Mount Marlow, North Gregory, Brandy Creek, Whitsundays, Cannovale, Jubilee Pocket, Cannonvalley, Strathdickie, Woodwark, Glenella, Shingley Beach, Sugarloaf, North Mackay, Gregory River and Riordanvale lost power about 10.18pm.
Monday night's outages were just the latest in a string of power failures across the state's north.
According to Ergon, 1362 homes lost power about 4.05pm in some parts of Riordanvale, Armstrong Beach, Cannon Valley, Woodwark and Cannovale.
By 4.15pm, another 85 properties had lost power due to cyclone damage in Shute Haven, Jubilee Pocket, Shute Harbour and Hayman Island in the Whitsundays.
At 8am, Ergon said 69 homes would remain without power due to work having to be delayed.
'Destructive core could take 18 hours to pass'
Earlier, the bureau's Queensland regional director Bruce Gunn said the situation was changing rapidly.
"Cyclone Debbie approaches a coastal crossing around 8am on Tuesday morning," he said.
"We can expect a very destructive core roughly about 100km across.
Residents hit by the brunt of the storm can expect to be waiting up to 18 hours for the huge core to fully pass.
"People in the path of the core of the cyclone can expect many many hours of sheltering," Mr Gunn said.
Premier Annastacia Palaszczuk offered her prayers to residents in the affected area, reiterating that the window of opportunity to leave was rapidly closing.
"This is going to be a very long night for a large number of Queensland families," she said.
"And from the outset, I want to offer my prayers to those families, and I know that every Queenslander is behind you, and that every Australian is behind you."
The "very destructive core" could pack wind gusts of up to 275km/h when it hits, according to the BoM. Debbie had sustained winds near the centre of 165km/h with wind gusts to 250km/hr by 8pm today, the BoM said.
Authorities say it could take up to 18 hours for the cyclone to pass, and that the core could be up to 100km wide.
The "warning zone" remains between Cardwell and St Lawrence, towns inland of Townsville and Mackay including Pentland and Moranbah are now in the "watch zone".
At 8pm it was positioned about 170km east northeast of Bowen and 195km north northeast of Mackay, moving west southwest at 9km/h.
The cyclone has already been linked to one death, with Police Commissioner of Queensland Ian Stewart saying a tourist died in a two-vehicle crash near Proserpine Monday morning, with weather conditions caused by Debbie a likely factor.
About 25,000 residents of low-lying Mackay were told Monday afternoon to evacuate ahead of fears of storm surges as a result of the cyclone.
The range of inundation at Mackay is expected to be between 0.8m and 2.5m above the highest astronomical tide as a result of the tidal surge, prompting the area's mass evacuation.
"This is probably the largest evacuation we've ever had to do," Premier Annastacia Palaszczuk told Ten News.
"This is going to be a monster of a cyclone.
Police Commissioner Ian Stewart said about 25,000 residents from low-lying parts of Mackay were urged to head south to at least Rockhampton.
"Don't wait until tomorrow because you won't be able to move probably past midnight tonight," he said.
He said there had never been so many people who had been urged to leave an area before.
"We have certainly moved whole towns before but nothing of this magnitude," he said.
"It will put a huge stress on traffic conditions," he warned. "I'd ask people to be very sensible on the roads ... drive to the conditions, take it easy, be patient and everybody will be able to get out safely."
Main Roads and Road Safety Minister Mark Bailey said it was important affected residents take the evacuation advice seriously and not lose sight of road safety.
"A female tourist has already lost her life in a two-vehicle crash near Proserpine this morning, we don't want to see this happen again," Mr Bailey said.
Ms Palaszczuk said she was "very concerned" at the prospective tidal surge.
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