Authorities could have predicted the deadly, city-wide outbreak of asthma and respiratory problems that took place during a thunderstorm in the Australian city of Melbourne on Monday evening local time, according to the researcher who first coined the phrase “thunderstorm asthma.”

Associate professor Cenk Suphioglu, an environmental allergist from Deakin University, told a local newspaper that a “perfect storm” of conditions triggered what one senior health official described as a “state disaster.”

Two young people died during the storm as a result of asthma triggered by the extreme weather, while ambulance services were overwhelmed by a massive spike in calls as thousands of residents struggled to breathe and hundreds were rushed to local hospitals.

“We’ve had a lot of rain, which means there’s a lot of grass, which means there’s a lot of pollen, Prof. Suphioglu told the Geelong Advertiser. The rain, he explained, broke up the pollen, releasing an abnormally high concentration of microscopic particles into the wind.

The size of the particles made it easy for them to enter airways and lungs, triggering adverse reactions in many people who had never experienced them before.

Professor George Braitberg, director of emergency services at Royal Melbourne Hospital, told another local paper, the Herald-Sun, that “Most people I saw weren’t asthmatics or hadn’t had it for 25 years. It was an extraordinary situation; the worse I’ve experienced in 30 years in the job.”

Around 1,900 calls were made to ambulance services during a five hour period and, at one point, calls were being received every few seconds. Several hospitals activated disaster management plans.

Nearly 500 children were brought to the Royal Children’s Hospital, with scores admitted. The state premier’s two sons suffered serious attacks.

The Herald-Sun reported the two fatalities as 18-year-old Omar Moujalled, who was just days away from his high school graduation, and 20-year-old Hope Carnevali, a law student who died on her front lawn while waiting for an ambulance to arrive.

According to the Age newspaper, dozens remain in intensive care and more deaths are likely.

Prof. Suphioglu said resources were needed to set up an alert system and prevent a recurrence of the tragedy. How seriously the authorities “take those alerts will be up to them,” he told the Herald-Sun.

State health minister Jill Hennessy said that a “full review” would launched.

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