Thunderstorm warnings and flood emergencies have been issued in parts of south-east Queensland as heavy rain continues to drench the state amid remnants of ex-Tropical Cyclone Alfred.

Emergency flood alerts have been issued and about 238,000 homes and businesses are without power in Queensland and New South Wales in the wake of Ex-Cyclone Alfred. It comes after severe winds lashed the Queensland's south east and heavy rains smashed coastal communities.

South East Queensland and northern NSW continue to experience thunderstorms, intense rainfall and flooding in the wake of Alfred. Follow our ongoing coverage.

Flood warnings are in place south of Brisbane, with a search and rescue operation underway for a missing 18-year-old in Logan. Hundreds of schools are still closed today with a severe thunderstorm warning in place. And two soldiers remain in a serious condition in hospital after an ADF vehicle crashed in northern NSW on the weekend.

Hundreds of thousands of people in Australia's Queensland state were without power on Sunday after Alfred, a downgraded tropical cyclone, brought damaging winds and heavy rains, sparking flood warnings.

Nearly 100,000 homes and businesses across Brisbane and the City of Moreton Bay have been left without power, with residents warned intense rainfall was still to come on Monday.

AMP chief economist Shane Oliver estimated the cost of the storm could be $1.1 billion a day based on the population of affected regions, but that was expected to be a “very short-term impact”. “Then you’ve got this flip side of that, the rebuilding kicks in and that acts as a stimulus,” Oliver said.

Brisbane is a subtropical city of more than 2.5 million people, situated on a flood-prone river. That’s why residents mustn’t get complacent after Cyclone Alfred.

Thousands of Queensland residents were left without power on Sunday after Cyclone Alfred, a downgraded tropical cyclone, caused widespread damage across the state.

Brisbane residents have relived their horror after a massive gum tree came crashing through their family home during cyclonic winds last night.

Tropical Cyclone Alfred's approach was coloured by slow, suspenseful movement. Here's how the weather event and emergency response unfolded.

Residents are stacking sandbags to protect low-lying properties ahead of a tropical cyclone that is forecast to become the first in 51 years to hit the Australian east coast near Brisbane, the nation’s third-most populous city.