Research previously suggested that low temperatures and humidity in winter create a favorable environment for transmitting the flu virus, but the 2017-2018 flu season was one of the warmest—and deadliest—on record. The Centers for Disease Control reported 186 children’s deaths that flu season.

FSU meteorologist Zhaohua Wu researched historical weather data in highly populated northern regions and found that extreme weather fluctuations during autumn months kick-started the flu. These findings implied that “the lapsed human immune system in winter caused by rapidly changing weather makes a person more susceptible to flu virus,” Wu says.

• Zhaohua Wu