Spring Allergies or Something More? What Australians Need to Know About Thunderstorm Asthma

October 20 2026, by Rachelle Seldon , 9 min reading time

Sneezing, itchy eyes and a runny nose? For many Australians, that's just part of spring. But when high pollen levels meet a thunderstorm, the consequences can be much more serious.

Spring means warmer days, backyard BBQs and spending more time outdoors. Unfortunately, it's also grass pollen season across many parts of Australia.

And there's one spring health risk that can catch people by surprise: thunderstorm asthma.

You don't necessarily need to have asthma to be affected, either.

Can a Thunderstorm Really Trigger Asthma?

It sounds unusual, but yes!

During high pollen conditions, certain thunderstorms can cause grass pollen grains to break apart, releasing tiny allergen-containing particles into the air.

Strong winds can concentrate these particles close to the ground, where they may be inhaled deep into the lungs.

For someone sensitive to grass pollen, this can trigger coughing, wheezing, chest tightness or difficulty breathing.

The surprising part? Someone who normally experiences only hay fever could suddenly develop asthma symptoms.

Thunderstorm asthma events are uncommon, but they can develop quickly and affect many people at once.

Why Spring Is Particularly Important in Australia

According to NSW Health, October through December is a higher-risk period for thunderstorm asthma, when grass pollen levels and thunderstorm activity can overlap.

In NSW, southern regions and the Riverina are areas of particular concern, although events can occur elsewhere when conditions align.

Victoria and other parts of Australia can also experience thunderstorm asthma risks during their grass pollen seasons.

Of course, this doesn't mean every spring storm is dangerous. A particular combination of pollen and weather conditions is required.

Have Hay Fever? Here's Why You Should Pay Attention

If you're someone who reaches for tissues every spring, this next part is worth knowing.

People with seasonal hay fever, particularly those allergic to grass pollen, may be at greater risk.

You may be more susceptible if you:

Experience hay fever during spring.
Have diagnosed asthma, even if symptoms are usually mild.
Have experienced asthma symptoms in the past.
Notice wheezing or coughing alongside your usual hay fever symptoms.

Never been diagnosed with asthma? That doesn't automatically mean you're in the clear.

If you regularly experience hay fever alongside wheezing or breathing difficulties, speak with your GP about whether you should be assessed for asthma.

5 Ways to Prepare Before the Next Spring Storm

The good news is that a few practical precautions can help reduce your risk.

1. Check the Pollen and Weather Forecasts

Before heading outdoors, particularly on windy days, check local pollen levels and weather warnings.

Useful resources include:

Bureau of Meteorology — weather forecasts and thunderstorm warnings.
Australian Pollen — pollen forecasts for participating locations.
Asthma Australia — asthma education and seasonal health advice.

2. Be Mindful of the Wind Before a Storm

If you have asthma or grass pollen allergies, avoid going outdoors when a thunderstorm approaches during high pollen conditions.

The gusty period before the rain can be particularly important.

3. Keep Windows and Doors Closed

If high pollen levels coincide with thunderstorms, stay indoors with windows and doors closed.

If your air conditioner has a recirculation setting, use it to avoid drawing outdoor air inside. Otherwise, switch the air conditioner off during high-risk conditions.

4. Don't Ignore Your Hay Fever

If spring allergies are a regular problem, speak with your pharmacist or GP about managing your symptoms.

Good hay fever management matters, but anyone with asthma also needs appropriate asthma treatment.

5. Have an Asthma Action Plan

If you have asthma, keep your reliever accessible, take your prescribed preventer medication as directed and ensure your asthma action plan is up to date.

Is Your Air Conditioner Ready for Spring?

When was the last time you cleaned your air-conditioning filters?

As temperatures rise, many Australian households start using their air conditioners more frequently. But after months of limited use, dust and debris may have accumulated in the filters and components.

Moisture inside poorly maintained systems can also create conditions where mould develops.

Keeping your air-conditioning system clean and properly maintained is an important part of looking after your indoor environment.

A Few Simple Ways to Improve Indoor Air Quality

Clean your air-conditioning filters

Check filters regularly and clean or replace them according to the manufacturer's instructions. Dirty or blocked filters can restrict airflow and affect system performance.

Check your air purifier

If you use an air purifier, consider one with a HEPA filter that's suitable for the room size.

HEPA filtration can help reduce airborne particles, including some pollen, dust and other allergens. Remember to check the manufacturer's recommended filter replacement schedule.

Air purifiers can support general indoor air quality but should not be relied upon to prevent thunderstorm asthma.

Keep an eye out for mould and musty smells

Air-conditioning coils, drainage trays and other damp areas can develop mould if moisture isn't properly managed.

If you notice visible mould or persistent musty odours, arrange appropriate cleaning or professional maintenance.

Use your air conditioner wisely during storms

When thunderstorms coincide with high pollen levels, keep windows and doors closed and use recirculation mode if available.

Give Your Air Conditioner a Spring Refresh

Keeping your air-conditioning system clean isn't just about cooling performance. It's also about maintaining a cleaner, more pleasant indoor environment.

The SAN-AIR range includes specialist products designed for air-conditioning systems, coils and air-handling equipment, helping address microbial buildup and odour concerns.

Whether you're refreshing a home air conditioner or maintaining a larger air-handling system, choosing products suitable for your equipment and following the manufacturer's directions is important.

Explore SAN-AIR Air Conditioning Solutions →

Is It Hay Fever or an Asthma Attack?

Hay fever commonly causes sneezing, itchy eyes, a runny nose and nasal congestion.

Asthma symptoms can include:

Wheezing or whistling when breathing
Tightness in the chest
Persistent coughing
Shortness of breath

If you're experiencing these symptoms, don't simply assume it's your usual spring allergy.

Follow your asthma action plan if you have one, and seek prompt medical advice for new or worsening breathing symptoms.

Severe breathing difficulties are a medical emergency. Call Triple Zero (000) immediately.

Can Wearing a P2 Mask Help?

P2 respirators are designed to filter certain airborne particles, including dust and smoke particles, when worn correctly with an appropriate fit and seal.

They're useful in suitable situations involving airborne particle exposure, including certain dusty environments and cleaning activities.

However, it's important to understand the difference between general respiratory protection and thunderstorm asthma prevention.

P2 masks should not be relied upon to prevent thunderstorm asthma.

According to Healthdirect Australia, face masks do not protect against the tiny particles responsible for thunderstorm asthma.

Staying indoors during high-risk conditions, managing asthma and hay fever, and following medical advice remain essential.

Spring Respiratory Wellness & Air Quality Essentials

While no household cleaning product, respirator or mucus-clearing device replaces proper asthma management, taking care of your indoor environment and supporting everyday respiratory wellness can still be part of your spring routine.

Here are a few products worth exploring.

SAN-AIR V3R Air Conditioning & Air Handler Reactive Gel

Is your air conditioner due for some attention?

Australian-made SAN-AIR V3R Reactive Gel is formulated for suitable air-conditioning and air-handling applications, helping address microbial contamination and odour concerns within compatible systems.

Available in different sizes for residential and larger air-handling applications.

Shop SAN-AIR Air Conditioning & Air Handler Gel →

SAN-AIR Hygiene HVAC-R Coil & Machine Cleaner Concentrate

Dust, dirt and microbial buildup can affect air-conditioning system performance.

SAN-AIR HVAC-R Coil & Machine Cleaner Concentrate is designed to clean compatible coils and internal components, helping support routine system hygiene and maintenance.

Ideal for appropriate residential and commercial HVAC applications, with cleaning carried out according to the product directions and equipment manufacturer's requirements.

Shop SAN-AIR Coil Cleaner →

AMD P2 Nano-Tech Respirator Masks

Heading outdoors on a dusty day or tackling a job involving airborne particles?

Australian-made AMD P2 Nano-Tech Respirators are designed to help reduce exposure to certain airborne particles when properly fitted.

Featuring lightweight nano-fibre filtration technology, they're available in different sizes and earloop or headband styles to suit different needs.

Important: P2 respirators should not be relied upon as protection against thunderstorm asthma and are not a substitute for prescribed asthma treatment.

Shop AMD P2 Respirators →

Kan-Breathe™ Mucus Clearing Device

Looking for a practical way to support your everyday respiratory wellness routine?

Australian-made Kan-Breathe™ is a compact, drug-free mucus-clearing device that uses Oscillating Positive Expiratory Pressure (OPEP) technology.

By creating gentle resistance and vibrations as you breathe out, it helps loosen mucus and support airway clearance.

Reusable, portable and easy to incorporate into an appropriate respiratory care routine, Kan-Breathe offers a convenient option for people who may benefit from mucus-clearance exercises.

Important: Kan-Breathe does not prevent or treat thunderstorm asthma or acute asthma attacks. Speak with your healthcare professional to determine whether it's suitable for your needs.

Shop Kan-Breathe™ Mucus Clearing Device →

A Little Awareness Goes a Long Way

There's plenty to love about an Australian spring, and most thunderstorms pass without causing widespread asthma problems.

But understanding the connection between grass pollen, spring weather and breathing difficulties can make an important difference.

If you or someone in your household experiences hay fever or asthma, now is a good time to review your symptoms, check your medications and make sure you know what to do if breathing becomes difficult.

And while you're preparing for the warmer months, don't forget to give your air-conditioning system and indoor air quality some attention too.

Enjoy the warmer weather — just keep an eye on what's happening in the air around you.