Another reason why I don't want to live in parts of the Midwest, South and East

[theking]

...The humidity makes the heat even worst than dry heat. For example, I'll take 110 degree dry desert heat in the west over 90 degree in the Midwest with high humidity. That muggy sticky feeling is just not good IMO:

It’s not the heat; it’s the humidity: Moisture increases heat risk in urban climates

Residents of major cities know that when summer rolls around, the concrete and lack of vegetation can lead to temperatures well above normal, but researchers believe there is growing evidence that humidity plays a larger role in the increasingly stressful environment.

A new study by experts at the Yale School examined the urban heat effect and its correlation with humidity. The study determined that some efforts to reduce the heat, either through trees or vegetation, were essentially erased due to the air’s moisture causing feel-like temperatures to soar.

"Green vegetation can lower air temperature via water evaporation, but it can also increase heat burden because of air humidity. The question then is to what extent this humidifying effect erases the cooling benefit arising from temperature reduction," Xuhui Lee, a professor of meteorology and director of the study, said in a statement.

The effects of urban heat impact the majority of the world’s population, with what the school estimated to be some 4.3 billion people who live in an urban setting.

Researchers found the enhanced stress caused by humidity more dominant over equatorial regions and points southward than in more temperate climates.

"In dry, temperate, and boreal climates, urban residents are actually less heat-stressed than rural residents. But in the humid Global South, the urban heat island is dominant over the urban dry island, resulting in two to six extra dangerous heat stress days per summer," Lee stated.

The World Economic Forum estimated that by 2050, 80 percent of the world’s population will live in an urban setting and be at risk for increased impacts brought on by heat.

Heat waves are the greatest weather-related killer in the U.S., and many countries, with hundreds of fatalities reported every year.

According to the Centers for Disease Control and Prevention, extended exposure to warm air can cause heat exhaustion and even a stroke.