Sodden or scorching? What the weather bureau is predicting for Brisbane’s summer

Brisbane is set for a summer of extremes, with the weather bureau predicting severe storm cells, above-average rainfall and unusually high temperatures, as well as one cyclone for the state.

The high-risk weather season has begun, with an early-November heatwave giving way to regular storms, heavy rain and flash flooding.

“In terms of the season ahead, we are expecting average to above-average rainfall … across much of the state,” senior meteorologist Kimba Wong said on Wednesday.

“While flooding is a seasonal risk, that risk will be elevated for some catchments across eastern Queensland, where we’ve already seen these wet conditions early in the season.

“We are also expecting warmer than average conditions to persist through the summer months. And, unfortunately, alongside this there’s an increased risk of unusually high temperatures and heatwave conditions as well.”

Summer-style storm cells are already ripping across south-east Queensland, with one dumping 50 millimetres of rain over Brisbane in just one hour on the night of November 13.

A low-pressure trough soaked the city on Wednesday and dumped nearly 100 millimetres over Caboolture in 24 hours.

The bureau has predicted more widespread rain and sporadic “hit and miss” thunderstorms for the already sodden state from December through to February.

Typically, three air masses collide – an inland trough, a southeasterly wind, and warm, moist northeastern air – to create volatile storm conditions. That was the reason some storms hit in the late afternoon, Wong explained.

Queenslanders were also warned that at least one cyclone would make landfall from December, and it may be severe due to warmer ocean temperatures.

“The sea surface temperatures around Australia and globally are at near record [highs],” Wong said. “As a result, we may see a high proportion of severe tropical cyclones developing this season.”

More storms are on the horizon.Credit: Felicity Caldwell

Four tropical cyclones typically form in the Coral Sea each year, she said, with at least one always crossing the Queensland coast.

Queensland Police Deputy Commissioner and State Disaster Co-ordinator Shane Chelepy said it appeared that residents were becoming storm-weary and not heeding warnings.

“We are seeing heavy rain, heavy downfalls. It’s what we expect [in] Queensland during [the] summer period. But ... we’re seeing our Queensland Fire Department swift water rescue crews already having to rescue drivers who have chosen to drive through floodwater, who are putting themselves, their families and our emergency services and volunteers at risk,” he said.

“We lose more lives through people taking risks, driving through floodwaters, than we do from the disaster. So please, if it’s flooded, forget it.”

State Disaster Co-ordinator Shane Chelepy has reminded Queenslanders that “if it’s flooded, forget it”.Credit: AP Photo/Mark Baker

Chelepy said flash flooding was more likely this season because rivers and creeks were already saturated.

“‘Get Ready Queensland’ starts with knowing your risk. It’s about knowing where you live and what the risk is in your area, and then understanding what you need to do as an individual living in that area.”

Queensland is Australia’s most disaster-prone state, with more than 120 calamities since 2011.

Premier David Crisafulli convened the Queensland disaster management committee on Wednesday to prepare for the severe weather season.

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