1. Health
You can opt-out at any time. Please refer to our privacy policy for contact information.

Extreme Weather - Asthma Trigger & Irritant

Impact of Weather & Climate Change on Asthma


Updated: June 4, 2008

Asthma triggers are substances or conditions in your environment that set off, or trigger, asthma symptoms in sensitive people. Generally, what are triggers to people with asthma are perfectly harmless to other people. It is basically a matter of your airways over-reacting to the trigger and setting off a number of changes in your airways that are associated with inflammation.

The purpose of this inflammatory response is to protect you from harm. But, in reality, you actually feel worse, because of symptoms like wheezing, coughing, shortness of breath and a tight feeling in the chest that makes it hard to breathe.

The most common kinds of triggers are allergens, such as pollen, dust, mold, or cats, or irritants, such as smoke or chemical fumes.

But, in some people, extreme weather conditions and changing climate conditions may also be an asthma trigger. This falls into the irritant category, meaning that your airways would likely already be inflamed from other triggers to some point before you would be sensitive to weather changes and experience further irritation.

Examples of weather changes that can further irritate already inflamed airways are:

  • Hot, humid weather
  • Extreme cold
  • Sudden changes in temperature, humidity or air pressure
  • Strong winds
  • Thunderstorms

Extreme Weather and Other Asthma Triggers

In addition, extreme weather can amplify, or worsen, the impact of certain other asthma triggers. For instance:

  • If you live in areas where forest fires are common during the summer months or where a phenomenon known as a temperature inversion happens during the winter months, then poor air quality may make things even worse.
  • During extremely hot, windy days, pollen counts are higher, meaning that more pollen spores are being carried from their sources into the air.
  • On hot, humid days, mold spore counts can be higher.
  • Exercising or doing activities outdoors on cold, dry days can bring on exercise-induced asthma symptoms or an asthma attack.
  • High winds often associated with thunderstorms can stir up and carry higher levels of fungal / mold spores too.
  • Hot weather tends to have a negative effect on air quality too. Heat and sunshine tend to decrease the ozone layer, which increases the levels of air pollution.

Climate Change & Asthma Triggers

Recently, there has been a focus on the relationship between climate change – what is known as "the greenhouse effect" – and asthma. The gradual warming of our climates worldwide are also believed to be a factor in the explosion of asthma.

Some of the effects of global warming that are related to asthma include:

  • Increased levels of pollen in the air
  • Earlier start to the growing season
  • Longer growing seasons
  • Faster plant growth
  • Increased air pollution

What You Can Do

If you notice that your asthma symptoms start up or worsen when the weather changes or it's very hot or very cold, then weather may be one of your triggers, and you should take steps to avoid the impact, or at least lessen it, as much as possible. For example:

  • Limit outdoor activities when pollen and mold counts are high, or during hot or cold weather.
  • Wear a scarf over your mouth in cold weather to warm the air before it hits your airways.
  • Always keep your rescue inhaler close by.
  • Add weather to your Asthma Action Plan.


"Can the Weather Affect My Child's Asthma?." June 2007. Kids Health for Parents. 31 May 2008.

"Tips to remember: asthma triggers and management." 2007. American Academy of Allergy Asthma & Immunology. 31 May 2008.

"The Impact of Climate Change on Asthma & Air Quality." North Carolina Asthma Program. 31 May 2008.

  1. About.com
  2. Health
  3. Asthma
  4. Triggers
  5. Irritants
  6. Weather and Asthma - Climate and Asthma - Extreme Weather as Asthma Trigger

©2014 About.com. All rights reserved.

We comply with the HONcode standard
for trustworthy health
information: verify here.