Rising temperatures and humidity are growing concerns

Research shows that the combination of temperature and humidity can get more dangerous faster than scientists previously believed. 

Scientists and other observers have become alarmed about the increasing frequency of extreme heat paired with high humidity, measured as “wet-bulb temperature.” A 2010 study estimated the wet bulb temperature of 95 F at 100% humidity or 115 F at 50% humidity as the upper limit of safety. Recently this limit was tested on humans in a laboratory setting and showed that the wet-bulb temperature is actually 88 F at 100% humidity or 100 F at 60% humidity.