When Thunderstorms Hit, Asthma Can Become an ER Nightmare

Has your asthma ever acted up during or shortly after stormy weather? Turns out, there’s a perfectly good reason for that. Research out today links thunderstorms to worsening asthma attacks.

Doctors at the University of Kansas Medical Center examined emergency department data from hospitals in the area. On days when a storm took place, they found, the typical number of asthma-related ER visits was substantially higher than on non-storm days. The findings suggest that people with asthma should take extra precautions when thunder is in the immediate forecast, the researchers say.

“The main takeaway is awareness,†lead author Diala Merheb, an internal medicine resident at KUMC, told Gizmodo.

Thunderstorm asthma

There have been reports of “thunderstorm asthma†epidemics dating back to the 1980s, which seem to more affect people with seasonal allergies, or hay fever. But the most dramatic incident yet occurred nearly a decade ago in Melbourne, Australia. In late November 2016, a thunderstorm appeared to cause a surge of asthma attacks that sent over 3,000 people to the emergency room, hospitalized nearly 500 residents, and killed at least 10.

Numerous studies have documented the phenomenon internationally since, including some in the U.S. According to Merheb, though, theirs is the first research to look for this link between thunderstorms and asthma in Wichita, Kansas, specifically. Importantly, Wichita is already known for having high rates of seasonal pollen allergy, and it’s currently the top-ranked city on the Asthma and Allergy Foundation of America (AAFA)’s list of “allergy capitals.â€

The researchers analyzed five years’ worth of ER data from three hospitals in Wichita, from January 2020 to December 2024. This data was then cross-referenced with meteorologic records of the area.

Across those five years, about 4,500 ER visits related to asthma were documented, while 38 storm days occurred in the region, encompassing just 2% of the total days during the study period. But a whopping 14.1% of all asthma-related ER visits took place on those storm days, the researchers found. On average, there were nearly 18 ER visits related to asthma per day during thunderstorms, compared to roughly three ER visits a day when it wasn’t storming.

The team is presenting its research this week at the annual meeting of the American College of Allergy, Asthma and Immunology. That means their work is preliminary for the time being, since the study hasn’t been published in a peer-reviewed journal yet. The authors also note that their results can only show a correlation between thunderstorms and asthma.

At the same time, the findings are only the latest to find a connection between these two things. “While this doesn’t prove cause and effect, it suggests that thunderstorm conditions, such as changes in wind or pollen dispersion, may play a role in triggering flare-ups,†Merhab said.

What does this mean for people with asthma?

Given what Merhab and others have found, it seems prudent for people with asthma and the doctors who treat them to be more cognizant of the potential risk.

“For people living with asthma, knowing that certain weather conditions can increase risk allows for more proactive management like keeping up with controller medications, and carrying rescue inhalers,†she said. “For clinicians, it reinforces the importance of discussing environmental triggers with their patients as part of routine asthma care.â€

Ironically enough, mild rain showers can actually lower people’s risk of seasonal allergies by simply washing away the pollen in the environment. Conversely, the causes of thunderstorm asthma appear to be more complex. Past research has suggested the strong winds of a thunderstorm can kick pollen or mold high up in the air, while the added electrical activity or moisture during a storm can break apart this pollen into smaller fragments more likely to cause a serious allergic reaction when inhaled.

But the arrival of a thunderstorm alone isn’t enough to routinely cause the sort of huge asthma surges seen during the 2016 Melbourne event. So there’s certainly more research needed to figure out the exact drivers of thunderstorm asthma— research that the authors are already looking to conduct.

“We’re hoping to build on these findings by looking more closely at local weather and environmental variables, things like wind patterns, humidity, and pollen data, to better understand what combination of factors might drive these events,†Merhab said.

In the meantime, if you have asthma and you see a thunderstorm on the way, that should give you even more motivation to stay firmly indoors if you can.