Ambulance in Melbourne
Ambulance Victoria was flooded with calls after a storm hit Melbourne shortly before 6pm.
A massive thunderstorm has caused an outbreak of asthma so severe emergency services in Melbourne ran out of ambulances to help those in need.

The enormous storm, which hit the Victorian capital at around 6pm on Monday, is believed to have led to a large scale occurrence of 'thunderstorm asthma' - where pollen and irritants swept into the air by the storm affect asthma sufferers.

In what was described as a 'major disaster', Triple Zero was so swamped by calls that Ambulance Victoria ran out of ambulances to help people.

It forced police officers and GPs to swing into action and help asthma sufferers across the city, The Age reports.

The head of Victoria's health services said he'd never seen an incident like it in more than 40 years as a paramedic.

'Every ambulance and ambulance manager was recalled,' Paul Holman said.

'It was an unprecedented night.

'I have never seen the computer dispatch of Melbourne look like it. It was what we call a sea of red.'

So sick were patients that the majority needed to be taken directly to hospital.

At one stage a reported 190 people were waiting from assistance from emergency services.

WHAT IS 'THUNDERSTORM ASTHMA'?
- 'Thunderstorm asthma' is caused when a large storm sweeps pollen and irritants into the atmosphere.

- The irritants cause asthma sufferers to have an attack.

- Rain and humidity can also stir irritants that affect asthma.

Source: Allergy Society Australia
In addition to widespread sickness, the wild weather also left a trail of destruction across Victoria with some residents reporting tornado-like conditions.

Thousands of homes in Melbourne's west were left without power, while homes were damaged and roads were closed because of fallen trees.

The SES received more than 350 calls for help across the state in the late afternoon.