Thunderstorm asthma

Thunderstorm asthma can be very serious for people with asthma. 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. 

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.  When exposed to this air, the tiny particles of pollen are breathed deep into your lungs, triggering an asthma flare-up or attack. 

You might have a higher chance of a sudden asthma flare-up triggered by a thunderstorm if you have:   

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

The risk of thunderstorm asthma is highest for 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. 

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 
  • ensuring you have all you need to be prepared, such as your asthma and hay fever medicines and apps, for the thunderstorm and pollen seasons.