Winds compared to a category one cyclone have damaged homes and uprooted hundreds of trees across a storm-hit region that is bracing for more wild weather.
A local mayor said gusts of up to 120km/h pummelled areas south of Brisbane as storms left a trail of destruction, sparking hundreds of calls for assistance.
Tens of thousands of homes were still without power late on Thursday in the wake of the supercells which triggered flash flooding and forced the closure of roads and more than 20 schools.
Logan, south of Brisbane, was one of the worst hit with some houses losing their roofs.
"We know now there were category one cyclonic winds coming through the city, with gusts up to 120km/h, and that's why we've got so much damage," Logan Mayor Jon Raven told AAP.
The mayor had just made it home when the storm struck late on Wednesday.
"I knew the wind was strong, because my horses turned around backwards and leaned into the gusts that were coming," he said.
"You know it's windy when your horses are leaning their butts into the wind."
He said the storm passed in 30 minutes, dumping 78mm of rain in the gauge by his horse paddock.
After the rain passed he returned to his city office, taking the long way because of fallen trees and power lines.
But with roads blocked, some people simply locked their cars and walked home, returning to their vehicles in the morning.
The mayor said 14 properties had been rendered temporarily uninhabitable due to structural damage, with occupants needing emergency accommodation.
Energex said about 25,500 homes were still without power by 3.30pm on Thursday.
The supercells dumped up to 100mm of rain on the region, with SES receiving more than 300 calls for help - with almost 240 of them in Logan.
Most were related to trees brought down by severe gusts that damaged homes and businesses, blocked roads and access to properties.
Energex warned hundreds of powerlines were down and some sections of the network would need to be rebuilt.
The storms kicked off what is expected to be a wet and wild end to the week across the southeast, with heavy rain forecast.
"We're in the middle of a big week of thunderstorms across southeast Queensland," the bureau's senior meteorologist David Crock told AAP.
Wet weather was set to continue into the weekend as moisture was dragged down from the tropics, bringing the further risk of flash flooding, he said.
