What is Thunderstorm Asthma?

Thunderstorm asthma can be very serious for people with asthma. 

Thunderstorm asthma events are thought to be triggered by an unusual mix of high levels of grass pollen and a certain type of thunderstorm. During these storms tiny pollen grains from grasses can be swept up in the wind and carried long distances.  

Thunderstorm asthma is also known as ‘epidemic thunderstorm asthma’. This means that many people develop asthma symptoms over a short period of time as a result of a thunderstorm. 

Since 1984, over 10 thunderstorm asthma events have occurred in Australia.  In 2016, a thunderstorm asthma event occurred in Melbourne, which claimed the lives of 10 people.

Where Do Thunderstorm Asthma Events Happen?

This map highlights the areas in blue that are more likely to have thunderstorm asthma events. 

The red dots on the map point to areas where the events have been recorded.

Locations affected by thunderstorm asthma. Map of eastern Australia overlay of Koeppen Climate Classification zones with places in that have experienced thunderstorm asthma episodes or thunderstorm asthma epidemics.

The peak time for thunderstorm asthma is mainly spring but can extend to December during the grass pollen season. 

Your local media may announce Thunderstorm Asthma Alerts on days when there is a high risk. 

Are You At Risk?

People at risk of sudden asthma flare-ups triggered by a thunderstorm include those with:  

• seasonal hay fever,   
• current asthma,   
• a history of asthma or   
• undiagnosed asthma.  

The risk of thunderstorm asthma is highest in adults who are sensitive to grass pollen and have seasonal hay fever (with or without known asthma). The worst outcomes are in people with poorly controlled asthma. Book a call with an Asthma Educator today to discuss your level of asthma control.  

To reduce the risk of thunderstorm asthma when it is a known trigger, it is best to have good asthma management year-round. This means: 

• Using your preventer during spring thunderstorm season 
• Keeping your hay fever under control 
• Checking pollen levels and where possible avoiding being outside on these days.

TIP: The best time to prepare is at least six weeks prior to pollen season, but it’s never too late to start:

• Make an appointment with your doctor
• Discuss your asthma and allergy management plan and,
• Ensure you have all you need to be prepared, such as medicines and apps, for the thunderstorm and pollen seasons.

Manage Your Risk of Thunderstorm Asthma

Here are some ways you can help manage your risk:

1. Do you need to see your doctor?

• Talk to your doctor about the need for inhaled preventer medicine for asthma and the best treatment for your allergies, including hay fever 

• Ask for a written Asthma Action Plan  
• Ask for a written Hay Fever (Allergic Rhinitis) Action Plan 
• Talk to your doctor about having allergy testing – in particular, grass pollen allergy testing. Allergen immunotherapy might be an option to consider with advice from your doctor

2. Be aware of thunderstorm forecasts particularly on HIGH or EXTREME pollen count days

• Use daily pollen monitoring/pollen count apps and/or websites, such as the Pollen Forecast website 
• For thunderstorm asthma forecasts and alerts in Victoria go to the Vic Emergency website 
• Where possible avoid being outside during thunderstorms in the grass pollen season – especially in the wind gusts that come before the storm. During a thunderstorm: 

• Go inside and close your doors and windows – at home or in your car, for example 
• If you have an air conditioner, turn it on to recirculate

3. Act early at the start of asthma symptoms

• Carry your reliever puffer with you at all times in grass pollen season. Know how to use it  – ideally with a spacer 
• Follow your written Asthma Action Plan if you have one, or if you don’t, use Asthma First Aid    
• Never ignore asthma symptoms like breathlessness, wheezing and tightness in the chest.  

Start Asthma First Aid immediately and call Triple Zero (000) for help if symptoms do not get any better or if they start to get worse. 

Flo, White Magic and echamber are campaign partners of Asthma Australia and have not been involved in the development of this webpage.