On February 28, floodwaters inundated parts of Brisbane, Queensland. The flooding in southeast Queensland had killed at least seven people. On Monday morning, police announced that a man died in floodwaters in Fitzgibbon, in Brisbane’s north. This is not the first time flooding in Brisbane and southeast Queensland has been flooded, but each event is unique and devastating in its own way.
This rain is being caused by a slow-moving low-pressure trough that has been sitting close to and occasionally over the southeast Queensland coast, according to Jackson Browne, senior meteorologist with the Bureau of Meteorology.
“Because of the system’s slow movement or even stationary nature,” he explained, “those rainfall accumulations really escalate.”
Normally, weather systems move from west to east across the country, but this trough has been stuck over southeast Queensland for days.
“In this case, we’ve had a blocking system, what we call a blocking high, that’s been sitting well to the east of eastern Australia,” Mr. Browne explained.
This system has not only lingered, but it has also brought unusually heavy rain and storms.
While there have been numerous transient small-scale lows, Mr. Browne believes a more substantial low formed on Sunday.
“It’s really encouraging what we call ‘convergence’ into the low,” he explained.
“That convergence is driving thunderstorms that are delivering that intense rainfall, particularly today but also, to a lesser extent, the previous two nights.”
“Today’s storms have really added insult to injury because you’ve got the heavy rainfall in the background.”
It doesn’t take much to cause flash flooding in an already saturated catchment.
Of course, we’re not just dealing with flash flooding right now; we’re also dealing with riverine flooding.
To begin with, no definitive comparisons for this event will be possible until the flooding has subsided.
More rain is forecast for this evening, rivers are still rising, water is still pouring down from Wivenhoe Dam, and high tides are still on the way.
This is not yet the end of the story.
The Bureau of Meteorology provides the most recent river and rainfall levels for those interested in getting a sense of how things are shaping up so far.
The Brisbane River Port Office gauge had risen above the moderate flood level as of 4:13 pm local time on Sunday, but the river was still rising.
The flood so far, at around 3 meters, falls short of the floods of 2011 and 1974. However, as of 7 p.m. local time, the BOM predicted that the river would reach 3.7 m on Monday morning.
Ms. Palaszczuk said on Tuesday that flooding in Brisbane received about 80% of the rainfall it normally receives in a year in just two to three days.
Over a meter of rain fell on more than 30 suburbs in the south-east.
The Brisbane level then peaked at 3.85m during high tide on Monday morning, the highest since the 2011 floods.
Flooding occurred in the Brisbane suburb of Windsor on Monday as a result of the severe weather.
On Monday, there was flooding near the ABC building on Brisbane’s South Bank.
On Monday, it is estimated that more than 18,000 homes in south-east Queensland were flooded, and nearly 60,000 homes in the region were without power.
The Brisbane River’s levels fell slightly after the peak on Monday morning, but there was little relief for flood-affected areas.
The river rose again during the evening high tide, reaching a height of 3.41m. The magnitude of the event, according to authorities, could not have been predicted.
And the weather event is far from over.
Thousands of homes in northern New South Wales have been flooded, and many residents are still stranded as the waters recede.
A severe weather warning for heavy rain and high winds along the NSW coast remains in effect, which could result in additional damage and flooding.
On Monday, there was flooding in Lismore.
A low-pressure system off the coast of New South Wales is also expected to cause moderate flooding in Brisbane parts of western Sydney.
The flood risk in southeast Queensland is also not over, with heavy rain forecast for the end of the week and this weekend.