The Bureau of Meteorology warns gales will continue across coastal and inland Queensland in the cyclone's path, and heavy rain may continue for 24 hours.
Cyclone Debbie is edging slowly inland having crossed the north Queensland coast between Airlie Beach and Bowen about midday on Tuesday as a category four system, bringing wind gusts of 260 kilometres per hour.
Some hours later it was downgraded to a category three, and on Tuesday evening became a category two system before becoming a category one around midnight.
One man was seriously injured today when a wall collapsed on him at Proserpine, south of Bowen. Emergency services fear further reports of injury and even death. Ms Palaszczuk said there had been reports of damage in places including Proserpine and other smaller communities between Bowen and Mackay.
"We're going to be getting a full assessment of the extent of the damage Wednesdaymorning at first light," she said. "Please stay inside, do not leave your homes until authorities give you the OK to do so."
On Tuesday evening the storm passed over the mining town of Collinsville, south-west of Bowen, as a category two system.
Ms Palaszczuk said Collinsville had never experienced a category two storm before.
Queensland Fire and Emergency Services Deputy Commissioner Mike Wassing said there were reports of structural damage in Collinsville. "We don't have any reports of any injuries or life impact which is good. The community has really bunkered down," he said. Collinsville resident Julie said Cyclone Debbie had made its presence felt in the town. "We're getting hammered something savage ... the wind is absolutely raging, roaring and hasn't let up for about three hours," she said.
Later in the evening, Julie said there had been "lots of complacency… people were thinking the mountains would protect us. "I'm shattered emotionally and physically. I've gone through the worst 24 hours I've experienced in my 53 years." Prime Minister Malcolm Turnbull said the Federal Government was working closely with the Queensland Government to deal with fallout. "We have put in place the biggest pre-deployment of the Australian Defence Force in advance of a natural disaster," he said. "We have Brigadier Chris Field who will be the recovery coordinator so we are working very closely together." The bureau said the system was expected to weaken further as it moved south-west, with winds rapidly weakening overnight, but heavy rain would continue in affected regions for up to 24 hours. On Wednesday, the remains of the system will curve to a more southerly track over inland Queensland. Widespread falls of up to 250 millimetres are expected in coastal catchments and further inland over the coming days.