Thunderstorm asthma is extremely rare. It occurs when high winds worsen asthma symptoms by drawing higher levels of pollen and pollution particles into the air.

Thunderstorm asthma happens when a thunderstorm increases already high pollen levels.

The condition is also known as epidemic thunderstorm asthma (ETSA) because events such as these can cause many people to develop severe asthma symptoms over a short period.

People sensitive to pollen or with conditions such as seasonal allergic rhinitis and asthma have a higher risk of thunderstorm asthma.

Additionally, the worst outcomes are in people with poorly controlled asthma.

This article looks at the causes of thunderstorm asthma, how a doctor diagnoses it, along with its symptoms, prevention, and treatment.

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The symptoms of thunderstorm asthma typically manifest as severe asthma symptoms, such as:

According to the American Lung Association, thunderstorm asthma can also cause severe and life threatening asthma attacks.

Signs a person is experiencing an asthma attack include their lips turning blue and difficulty breathing or labored breathing, making it difficult for them to speak in full sentences.

Overall, being aware of asthma triggers can help prevent an asthma attack or reduce its severity.

While researchers are still trying to learn more about the causes of thunderstorm asthma, evidence suggests a link between asthma and environmental factors such as air pollution.

Thunderstorm asthma refers to when a combination of a thunderstorm and high pollen levels trigger a person’s asthma symptoms.

While some people with asthma find that rainy weather lowers their asthma symptoms, for others, stormy weather is a trigger.

Thunderstorms can worsen asthma due to the following factors:

  • Cold downdrafts concentrate air particles such as pollen and mold.
  • Wind, humidity, and lightning break up particles to a size that people can inhale through their noses, sinuses, and lungs.
  • Wind gusts further concentrate the small particles, causing people to breathe in large amounts.

A 2022 study showed that 65% of people with seasonal allergies experienced thunderstorm asthma symptoms, and nearly half who had an asthma attack required hospital treatment.

This suggests that people with seasonal allergies have a higher risk of developing ETSA. Among people with allergies, risk factors for experiencing ETSA include:

  • having poorly controlled asthma symptoms
  • getting a low score on a breathing test for asthma
  • having a high eosinophil count (a type of blood cell that relates to allergies)
  • having higher levels of lung inflammation
  • experiencing higher levels of ryegrass pollen in the atmosphere

ETSA events are rare and more likely in countries such as Australia, where grass pollen levels peak between October and December.

It is important to note that not everyone at high risk will experience an asthma attack. Moreover, people without these risk factors can also develop ETSA.

When making an asthma diagnosis, a medical professional may consider a person’s symptoms, family medical history, and personal medical history.

They may also conduct the following tests to help diagnose asthma:

  • a physical examination to check for signs of airway obstruction, asthma, and skin allergies
  • lung function tests to assess how well the lungs are working
  • other tests such as allergy testing, blood tests, and tests to determine how certain factors affect a person’s breathing

When a doctor makes their diagnosis, they will also note the type of asthma a person has on the basis of their triggers.

It may be helpful for a person to keep a log of their symptoms and possible triggers to help the doctor reach an accurate diagnosis. This can include information about potential irritants in their home, school, or workplace.

Asthma treatment typically involves prescription medications, such as inhalers, to relieve the symptoms. A doctor may also work with the person to devise an action plan explaining how to routinely manage symptoms and what to do if a flare-up occurs.

Occasionally, a person may experience an asthma attack requiring urgent first aid or medical attention, depending on symptom severity.

Symptom severity levelSteps to follow
Mild to moderate:

• minor difficulty breathing
• able to speak in full sentences
• able to move around
• may wheeze or cough

• Ask the person if they are asthmatic and require assistance.
• If so, administer asthma first aid.

• obvious breathing difficulties
• unable to speak a full sentence
• tugging of the skin between the ribs
• may wheeze or cough
• reliever medication not lasting as it should

• Call the local ambulance number.
• Commence asthma first aid.
Life threatening:

• gasping for breath
• unable to speak or 1–2 words per breath
• confused or exhausted
• turning blue
• collapsing
• no longer wheezing or coughing
• not responding to reliever medication
• Call the local ambulance number.
• Commence asthma first aid.

As reactions to environmental conditions during a thunderstorm are unpredictable, the best way a person can stay safe is by controlling asthma or seasonal allergies throughout the year.

During and before spring, a person should follow these precautions:

Before springtime

  • Look out for symptoms such as wheezing and sneezing, and see a doctor to discuss possible asthma signs.
  • Avoid known asthma triggers.
  • Use preventer medication regularly as directed by a health professional.

During springtime

  • Stay indoors before, during, and after storms, and keep windows closed.
  • Have a current asthma action plan.
  • See a doctor about medications to use to manage asthma symptoms.
  • Stay alert to the symptoms of wheezing, coughing, chest tightness, and breathing difficulties.
  • Recognize the signs of an asthma attack or rapid escalation, and seek urgent care in cases of emergency.
  • Try and carry an asthma reliever at all times.

People with allergic rhinitis, who have a greater risk of developing thunderstorm asthma, may find it helpful to check weather forecasts. Knowing a storm is coming can allow a person to prepare and ensure they have a sufficient supply of allergy or asthma medication on hand.

A person should also avoid going outdoors until the storm passes.

Thunderstorm asthma happens when high winds draw higher levels of pollen and pollutants into the air. The particles are so small that a person can easily inhale them into the lungs, which can trigger asthma symptoms.

If a person experiences asthma symptoms such as chest tightness, wheezing, shortness of breath, or coughing, they should see a doctor.

Daily usage of preventer medication, particularly when pollen counts are high or during stormy weather, can also reduce a person’s risk of developing thunderstorm asthma.