Authorities are warning residents to brace for more wild weather, after two major systems hammered south-east Queensland and northern New South Wales yesterday.
The Bureau of Meteorology is forecasting producing large hail and strong winds for the region this afternoon, and Energex has already reported almost 1,000 lightning strikes this morning.
Senior Forecaster Jonty Hall says the instability will stretch throughout Queensland, with storms also expected in central, north-west and far north parts of the state.
"Unfortunately we are still looking at a potent set up for south-east Queensland. I would think there's a pretty good risk of pretty dangerous storms around this afternoon and first part of this evening," he said.
Bureau of Meteorology senior forecaster Peter Otto says all the ingredients are right for storm activity.
"There's an upper trough over south-east Queensland giving the atmosphere a fair bit of energy and there is some humid air coming from the Coral Sea," he said.
The bureau is monitoring a severe storm cell south west of Gayndah in the Burnett region which is heading towards the town.
Another severe storm near Kooralbyn in the Scenic Rim is moving east and is expected to affect the area from Boonah to Canungra.
And there is a more general warning for the Wide Bay and Burnett, Darling Downs and Granite Belt, Southeast Coast and parts of the Central Highlands and Coalfields, Capricornia and Maranoa and Warrego districts.
Swathe of destruction
Repairs are underway in Brisbane after the wild electrical storms ripped through the city, uprooting trees, causing blackouts, flash flooding and damage to homes and buildings.
There have been 66,000 power interruptions in the last 24 hours and a few hundred homes are still waiting for electricity to be restored.
Energex reports that there have been more than 33,000 lightning strikes the storms first hit.
The first severe cell swept through the region yesterday morning, with a second line of storms passing overnight.
At Pittsworth and Millmerran on the Darling Downs there were reports of hail as big as golf balls and rockmelons.
Parts of Brisbane were hit with hail, while shops in the inner western suburb of Paddington were flooded.
Michaela Minx, the manager of the Kelvin Grove Markets in inner city Brisbane, said tents and stalls were flattened.
"There was a lot of tents that were mangled and destroyed and a lot of stock that, as you can imagine, was ruined," she said.
"It was quite horrific. There was a lot of terrified people, [and] a lot of people were in shock because it did hit quite fast.
"We have had cars that have had trees fall over on top of them, so the severity was definitely there."
Windsor State School principal Stephen O'Kane said two buildings and one classroom were badly damaged by falling trees.
"Half of the building has structural damage and will need to be repaired," he said.
"Two buildings have got trees on top of them and also some of the magnificent trees that we've got have come down as well."
Emergency services received 127 calls for help in the last 24 hours. A spokeswoman says most of the calls involved leaking roofs.
Mr Otto says up to 40 millimetres of rain fell within half an hour in east Brisbane during last night's storm.
"The storms didn't have the structure or strength like the ones in the first wave that came across yesterday morning," he said.
"Totals have been up around 100mm in the Lockyer Valley [west of Brisbane] and generally in Brisbane 60-80mm."
Northern NSW hit
In northern New South Wales the extreme weather destroyed at least one house and severely damaged a dozen others.
The village of Woodburn, south of Ballina, was hardest hit when the storm hit about 7:00pm AEDT last night.
In NSW, the SES has received at least 90 calls for help across the state's north.
It has been advised that power for about 2,000 properties could be out for up to 48 hours because major power lines have come down.
SES acting region controller Kaylene Jones says strong winds and hail wrought havoc.
"There are between 12 and 14 houses that we're aware of at this point in time that have substantial structural damage," she said.
"So that's either entire rooves have been taken off, some walls are blown out and damaged and so on.
"Those houses are quite uninhabitable. There is one house that's completely collapsed."
Authorities predict it could take several days to clean up after the severe storm.
Woodburn resident Stewart Rofe was in his house when it was destroyed by the storm.
"I was watching this storm come over and I said to the family, 'we're going to get a nasty one' - and it just got worse and worse and then the hail happened," he said.
"I can't believe it. The roof's two doors over, brand new roof...in a tree. Missed the house next door...House is gutted all the way through."
Another resident, Alison Smith, whose house was severely damaged, says it is lucky her family was out when the storm struck.
"I'd hate to think, my two girls and my husband, would have been probably severely injured. It basically tore our whole our whole roof off our house and debris everywhere. Yeah, nothing left inside our house, everything is gone," she said.
© ABC 2012
01:42 EDT Parts of Sydney have been lashed by a storm on Monday afternoon which resulted in ambulance crews treating several people who were struck by lightning.