Five storms had combined into one in Melbourne, bringing crazy weather conditions and causing exploded rye grass pollen to form into tiny particles.
The particles caused incredibly dangerous asthma symptoms for those in the area, causing the death of nine people.
Hope Carnevali was one of the nine to lose their lives that day. Her mother, Danielle, called the ambulance immediately when Hope showed signs of distress, but emergency services didn't arrive until 30 minutes later. By that time, it was too late.
"The hardest part for me as a mum is I had that chance of saving my daughter's life taken away from me," Danielle said on 60 Minutes last night.
"Had I been told that an ambulance wasn't in the vicinity, it wasn't dispatched, they had none left, I would have put her in that car in a heartbeat."
"I would have had her at that hospital, which is about six minutes away, and she would still be here with us today."
"I have to live with that guilt because she asked me to help her, and I didn't help her."
Danielle said her daughter started turning blue, and begged her mother for help before she took her final breath. Her devastated family attempted CPR on the front lawn as they waited for help to arrive, but Hope could not be revived.
"[She said], 'Mum I'm dying, mum I can't breathe, mum help me.'"
"To not be able to help her, as a parent that is the hardest thing you can ever go through."
8500 people were taken to hospital due to the storm, making it the most severe case of thunderstorm asthma ever recorded anywhere in the world.
"We intended to get to everyone possible - you call us, we will come," Ambulance Victoria's director of emergency management, Paul Holman, told the show.
"But the need was "unprecedented", with a call for help being made every four seconds during the storm."
Following last night's programme, Asthma Australia issued a statement to people who suffer from asthma and hay fever.
"The thunderstorm asthma event was an unprecedented and tragic episode," it read. "Proactive steps that can be taken to improve management of asthma or hay fever symptoms are to consult a GP, pharmacist or call 1800 ASTHMA."
This article first appeared on Marie Claire.