Queensland Ambulance Service says patients had to be moved due to the damage to the roof of Eden Private Hospital at Cooroy, on the Sunshine Coast, on Wednesday night.
"The building's roof suffered storm damage and was deemed structurally unsafe," QAS said in a statement.
Cooroy has recorded more than 110mm of rain since 9am on Wednesday with severe thunderstorms lashing large parts of the state's southeast with power lost to 11,000 overnight.Â
The Bureau of Meteorology says a trough will push east in coming days bringing potentially severe thunderstorms and localised flash flood possible from Thursday.
A flood watch has been issued for the Burrum and Cherwell, Mary, Logan and Albert Rivers, Condamine, Macintyre, Weir, Moonie, Balonne and Wallam rivers, and Mungallala creek.
"Parts of the region are wet following recent rainfall, with showers and thunderstorms over the next few days expected to saturate catchments, which may lead to river level rises," the forecaster said in an alert.
"River level rises are expected, with minor to moderate flooding possible across the Flood Watch area from Thursday afternoon."
Logan and Ispwich, south of Brisbane, are still cleaning up after a supercell storm also lashed the two cities on Tuesday afternoon.
The supercell damaged homes, causing one to catch fire, and cut power for more than 15 hours in Ipswich, before merging with another severe storm to cause more destruction at Logan.
"A small tornado was spotted at Logan which caused a lot of damage to houses with trees down and gusts reaching more than 90km per hour," Ms Pagel said told AAP on Wednesday.
The clean-up continued in Logan on Wednesday, with 15 properties significantly damaged including six that lost their rooves, cars hit by flying debris and fallen trees downing power lines in at least 10 suburbs.
Thunderstorms on Wednesday signalled the end of the three-day heatwave along the state's east coast from Townsville to Coolangatta.
Ms Pagel used Brisbane as an example of the "oppressive" conditions Queenslanders have endured this week.
"The night time temperature on Tuesday for Brisbane was 34 degrees but felt like 43 - even for Brisbane that is incredibly high," she said.
9°C