Melbourne, Victoria, November 2016

Thunderstorm Asthma, 2016

Quick Statistics

9 Fatalities
8000 Injured

At 1.58pm on 21 November, the Bureau of Meteorology issued a severe thunderstorm warning for Victoria's Mallee, South West and Wimmera regions, and parts of Northern Country districts, for damaging winds, heavy rainfall and large hailstones. At 4.00pm, the warning was extended to other areas including Geelong and Melbourne.

The temperature had climbed to 35 degrees Celsius – the state's hottest day since March. A Total Fire Ban was declared for the Mallee region. In response to these circumstances, the State Control Centre was operating at a Tier 2 readiness level. 

At 5.00pm, the gust front reached Geelong and moved quickly over Melbourne's metropolitan area, as many commuters were travelling home. The pollen count was high due to the combination of hot, dry northerly winds and rye grass to Melbourne's north and west. The moisture from the storm is thought to have caused the pollen to break into smaller particles, more able to penetrate a person's lower airways and cause an asthmatic reaction. 

That evening, the Emergency Services Telecommunications Authority (ESTA), Ambulance Victoria and hospitals emergency departments around Melbourne were faced with an unprecedented volume of asthma and other respiratory distress cases. Though the number of Triple Zero (000) calls eventually decreased, the call volume was still 147 per cent above the forecast between 9.00pm and midnight. It was 13 hours until Triple Zero (000) calls for ambulance services dropped below forecast numbers, at around 7.00am on 22 November. Even after that, hospitals and other health providers faced an unusually high volume of presentations related to breathing problems. 

Though primarily a health emergency, this event impacted the Metropolitan Fire Brigade (MFB) in its Emergency Medical Response (EMR) capability. The event saw an increase in EMR calls, and the MFB also provided 11 emergency responses to support Ambulance Victoria.

The Victorian Department of Health and Human Services has attributed nine deaths to this thunderstorm asthma event.



This incident was included in the Major Incidents Report 2016-17 (Australian Institute for Disaster Resilience, 2017). The report acknowledges the following sources:

Bureau of Meteorology, Monthly Weather Review November 2016.
Inspector-General of Emergency Management, Victoria, Review of response to the thunderstorm asthma event of 21-22 November 2016 – Final Report, 2017.
Victorian Government Department of Health & Human Services, 'Epidemic thunderstorm asthma,'