Parts of Brisbane have been submerged by flash flooding, with more storms predicted for south-east Queensland.
Bureau of Metereology (BOM) senior meteorologist Angus Hines said massive rainfall totals were recorded, with the heaviest falling inland from the Gold Coast.
In a short burst of rapid rainfall on Sunday, 51 millimetres were recorded in Brisbane City over 30 minutes.
In an hour, Rosalie saw 70mm and 77mm fell in Holland Park West.
Coombabah on the Gold Coast had 77mm and Waterford in Logan recorded 57mm in the space of under four hours.
Up to 265mm of rain hit Springbrook National Park and the wider Scenic Rim in the 24 hours to 9am on Sunday.
“Very, very wet there [and] caused some sharp river level rises including the Logan River, which shot straight into major flooding overnight,” Hines said.
“Anywhere that gets 200mm of rain or more in a 24-hour period is going to lead to some flash flooding, which can of course push water over roads and damage properties and businesses.”
The short burst of heavy rain caused flooding in parts of Brisbane, including Woolloongabba.
Photo: ABC News / Emma Pollard
The SES were called out to 70 storm-related jobs in the 24 hours from 5am today, mostly in the Moreton Bay, Ipswich and Gold Coast areas.
BOM issued a major flood warning for the Logan and Albert Rivers, with several moderate and minor warnings also in place across southern and south-east Queensland.
“We saw some pretty widespread rainfall of about 100-200mm across large parts of the south-east,” Hines said.
Wyaralong dam is beyond 100 per cent capacity and is currently spilling over.
Saturday’s “fairly extensive wet weather” impacted much of the state, but the other totals were much lower than in the south-east – between 20 and 50mm fell across the Darling Downs, up into the Highlands and parts of Far North Queensland.
The Wyaralong Dam, a spillway in south-east Queensland, spilling over.
Photo: ABC News
Mixed weather forecast
Severe thunderstorm warnings have been issued for parts of the state, as police advise road users to avoid the Lamington National Park due to “multiple rock slides”.
“There’s a chance of shower or thunderstorm, all the way from the top of the Cape York Peninsula right down to Brisbane and the Gold Coast,” Hines said.
“It’s likely to be a bit hit and miss, with some breaks in the showers, some sunshine and dry weather in the mix today.”
He said “pockets of heavy rainfall” are possible again, with potential for some damaging winds.
Storms will drop the mercury slightly, but BOM said cloud cover will invite the humidity to hang around.
“So as soon as that storm clears up and temperatures start to climb again, it’s going to feel just as sticky again,” Hines said.
Five people were rescued after fast, rising floodwaters left them trapped near Mudgeeraba,
Photo: Supplied / Queensland Fire Department
Humidity bends rainbow
A unique rainbow formed over a regional Queensland town on Saturday evening, with Hines describing the optical illusion as “virga”.
Inconsistent winds meant rain couldn’t fall in a straight line at Roma, giving the illusion of a bend when paired with sunlight and wind.
“It appears a rainbow is visible where the sun is striking virga droplets,” he said.
Virga forms in the clouds and is similar to regular rain except, as it falls towards the ground, “it evaporates away into nothingness”.
“All the liquid from the raindrops evaporates and nothing reaches the surface, so if you’re standing on the ground it won’t feel like it’s raining, but there is still wet weather falling,” Hines explained.
“In this instance, the virga appears to be falling out of the clouds and then getting blown into a slightly funny shape.
“That can often be because there’s some wind shear – different winds at different heights in the atmosphere – blowing the droplets around at different speeds.”
“The rainbow is the same shape as every rainbow, but the canvas upon which we view it is crooked,” Hines said.
The conditions needed for virga
The position of the sun, cloud, and on-ground observer all impact the chance of virga producing a rainbow and, while Hines said the phenomenon “certainly doesn’t happen all the time”, it will occur “if the conditions are right”.
That means having enough humidity to form the rain cloud that drops the virga, as well as “a little bit of dryness to promote evaporation”.
“It can’t happen in a very dry environment, but funnily enough virga also couldn’t happen in a completely moist, really highly humid environment [either] because there wouldn’t be enough evaporation on the way down,” he said.
“If it’s really humid and sticky … then that virga would just keep on falling, hitting the ground to become rain.”
The conditions aligned for the southern inland region of Maranoa on Saturday – where the rainbow was pictured at the Roma Country Music Festival – with the BOM recording 95 per cent humidity at Roma by 3pm.
It was the town’s highest humidity reading for November, and Hines doesn’t expect the sticky conditions to ease any time soon.
The sticky conditions were expected to continue, so Queenslanders were urged to try and stay cool.
Photo: ABC News / Elloise Farrow-Smith
Humidity to continue
Virga can be described as a by-product of Queensland’s wet season, with increased rainfall improving the chance of appropriate weather conditions, according to Hines.
“You’ll still need a bit of luck to see [a distorted rainbow] but, as we head into the wetter parts of the year, virga is certainly more likely,” he said.
“[We’ve seen] significant rainfall for the last few days, but last night we did see the most intense rain affect south-eastern parts of the state.”
Hines said, while rainfall could cool things off a little, it’s “unlikely to do anything to quell the humidity”.
“It’s staying very sticky and humid, basically it’s going to be humid whether or not it’s raining today,” he said.
“We’ve got some pretty oppressive conditions, with high dew points and lots of moisture in the atmosphere.”
That will fuel humidity “throughout the majority of Queensland”.
– ABC