A man was hospitalised in a critical condition after he was struck by lightning at Brendale, north of Brisbane, on Sunday afternoon as thunderstorms rolled across the southeast.
In the northwest, an extended period of extreme rain led to almost 100 residents being evacuated in remote Burketown after river levels exceeded seven metres, surpassing the 2011 record of 6.78 metres.
Thirty-seven houses had power disconnected as they were inundated in floodwaters, while about 70 residents remained in the area with limited electricity and water supplies.
Burke Shire mayor Ernie Camp said water levels had dropped on Sunday night, bringing some positive news for the flood-ravaged region.
"We do live in a quite extreme part of Australia. The flooding event has broken all records ... the First Nations people no doubt would have seen something much higher than this, but certainly in living memory it's the highest we've seen," he told Seven's Sunrise program.
Severe flooding is continuing along the Gregory, Nicholson and Leichhardt river catchments, which recorded up to 35mm of rain in the 24 hours to Sunday morning.
A major flood warning is also active in the lower Flinders and Cloncurry rivers.
The Gregory River peaked at 12.3 metres and was falling on Monday morning, although it remained at major flood level.
With more showers and isolated thunderstorms forecast for the state's northwest, emergency services expect peak flooding to continue.
Queensland Emergency Services Minister Mark Ryan said there was extensive damage in the state's northwest after daily rainfall reached in excess of 300mm.
"This has caused significant damage to road infrastructure, with large washouts and ground saturation triggering the closure of a number of roads," he said.
On Sunday, the federal and state governments announced more disaster funding, including payments for Urandangi residents of up to $180 for individuals or $900 for families to cover personal essentials.
In Burke, Carpentaria, Cloncurry, Doomadgee, Mornington and Mount Isa, loans of up to $250,000 are being made available for affected small businesses and primary producers.
"This weather event has been impacting Queensland for several months, and as conditions escalate, we're working with the Queensland government to ensure appropriate levels of community assistance are available," Emergency Management Minister Murray Watt said in a statement.
Scattered thunderstorms were also expected in southeast Queensland on Monday after heavy rain hit much of the region on Sunday afternoon.
About 70mm of rain fell in an hour at Imbil, south of Gympie, while 67mm was recorded in Samford near Brisbane.
The Bureau of Meteorology said there was a chance of severe thunderstorms between Mackay and the Sunshine Coast, and in the northern interior, on Monday.