Thunderstorm asthma: what is it and how do you protect yourself from it?

thunderstorm brewing over a grass field

Danny Baggs

Posted December 09, 2022

Storm season can cause damage to your home and belongings, and can also impact your health.

On 21 November 2016, during a thunderstorm with high pollen counts, thousands of Victorians suddenly found in hard to breathe and needed urgent asthma treatment. So many people needed help that it was hard for ambulances and hospital emergency rooms to treat everyone. 10 people ended up losing their lives.

Thunderstorm asthma is a very real and serious risk during Australia's summer storm season from October to December. This year, excess grass growth, high levels of airborne pollen and wet weather are creating optimum conditions for another possible thunderstorm asthma epidemic.

Read on to learn more about thunderstorm asthma, whether you're at risk, and how to prevent and treat thunderstorm asthma attacks.


woman wiping eyes with an inhaler in hand as she stands under a blooming tree

Thunderstorm asthma can impact people who don't have diagnosed asthma. Image: Getty

What is thunderstorm asthma?

Thunderstorm asthma typically occurs when a storm hits on a hot, windy day with high grass pollen counts.

Ryegrass pollen grains are swept up into the clouds as a thunderstorm forms. As the pollen absorbs water, the grains swell and burst open into tiny particles that contain pollen allergens. Storm winds carry these burst pollen particles over long distances before they are pushed down to the ground.

Since the pollen particles are so small, people inhale the particles deep into their lungs without noticing. Shortly afterwards, they are more likely to experience an asthma attack - whether they have diagnosed asthma or not.

Symptoms of thunderstorm asthma include:

  • shortness of breath
  • tightness in the chest
  • wheezing: a high-pitched sound when you breathe
  • persistent coughing


Mother giving her son an asthma inhailer

Strong winds that disperse pollen in storms can cause major breathing problems for people with asthma. Image: Getty

Who is at risk of thunderstorm asthma?

The National Asthma Council Australia Chief Executive Siobhan Brophy says people with asthma, hay fever and other respiratory problems can be at risk when strong winds, thunderstorms, bushfire smoke, dust storms and high pollen counts hit over summer.

That said, you may be at risk of thunderstorm asthma even if don't currently suffer from asthma. In fact, Asthma Australia reports that 36-44 per cent of people who present to an emergency department with thunderstorm asthma had never previously had asthma.

That said, certain groups of people are more likely to experience thunderstorm asthma. These include:

  • people with asthma, a history of asthma, or undiagnosed asthma
  • people with hay fever (allergic rhinitis)
  • people who are allergic to grass pollen, particularly ryegrass pollen.

People living in south-east Australia (Victoria and eastern New South Wales) are most likely to experience thunderstorm asthma epidemics, especially during the October to December grass pollen season. It doesn't matter whether you live in metropolitan, regional or rural areas, as the pollen can travel long distances.


man about to take inhaler

Prevention is better than treatment, but keeping a reliever puffer handy is always a good idea. Image: Getty

How do I protect myself against thunderstorm asthma?

The National Asthma Council says that asthma sufferers need preventive medication well before springtime thunderstorms and the pollen season.

These medicines usually consist of inhaled corticosteroids that help protect you from severe asthma attacks, like those that occur during thunderstorm season. They consist of preventer inhalers that are used every day, plus an inhaler to take when you experience symptoms.

If you suspect you may have asthma, visit your GP and discuss your symptoms with them. They will prescribe you the necessary reliever puffers and preventive medicines. They should also write up an Asthma Action Plan with you, so you know what to do during an asthma flare-up or emergency.

Make sure to keep your prescriptions up to date and to carry your puffers and medications with you, especially during spring and summer. During this time, you should also keep an eye on pollen counts and weather forecasts to be forewarned of possible thunderstorm asthma epidemics.

The Melbourne Pollen Count and Forecast, which is run by the University of Melbourne's School of BioSciences, is a great resource for asthma and hay fever sufferers. It provides a forecast for grass pollen levels in the air around Victorian regions, as well as an epidemic thunderstorm asthma forecast, so you can prepare in time. You can also download the Vic Emergency app and set up a 'watch zone' for your location to make sure you're notified of the risk of an epidemic thunderstorm asthma event occurring.

When the wind picks up before a storm, get inside and stay inside during the entire storm. Face masks can't protect you from the tiny pollen particles. Keep all windows shut and switch any air conditioners to recycle/recirculate.


woman in orange shirt holding an inhaler

Reliever puffers are inexpensive and easily accessible in Australia. Image: Getty

How do I treat thunderstorm asthma?

It's important to know how to deliver asthma first aid in case you or someone around you begins having a flare-up or attack, especially during the storm season.

If you start experiencing thunderstorm asthma symptoms and you do not have an inhaler or other reliever medication handy, call triple zero (000) immediately. Tell the operator you are experiencing an unmedicated asthma emergency and that you need an ambulance.

If you have a blue or grey reliever puffer (the most common type), follow these four steps:

  1. Sit upright and shake the blue or grey reliever puffer.
  2. If you do have a spacer, put one puff into the spacer and take four breaths from the spacer. If you don't have a spacer, inhale one puff with a deep, slow breath and hold your breath for as long as comfortable before exhaling. Repeat three more times.
  3. Wait four minutes and give four more puffs if you still can't breathe normally.
  4. Call an ambulance if you still can't breathe normally after the second round of inhales, continuing to deliver four puffs every four minutes until the ambulance arrives.

You can view instructions for other types of reliever puffers at Asthma Australia.


rain pouring off rain gutter on an Australian house

Try to get inside before the storm hits. Image: Getty

How do I protect myself from storms?

Summer storms are common across Australia. As we experience another La Niña weather event, you may notice storms becoming heavier and more frequent.

From flash floods to blackouts, storms can wreak havoc on Victorian homes and health. The best way to stay safe this summer storm season is to learn how to manage stormy weather and preparing ahead of time to protect your home from floods or protect your car from hail damage.

You can also refresh on how to drive safely in wet and stormy conditions, remembering to never drive through flood waters.

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