Would you prefer 88 degrees with 60 percent humidity or 98 degrees with 20 percent humidity? Ok, that was a trick question because according to the heat index measurement of what the temperature feels like to the human body when relative humidity is combined with the air temperature, both result in a feels-like temperature of 95 degrees.
How can this be? At 88 degrees and 60 percent humidity, the atmosphere has a more difficult time evaporating the sweat off of your skin, making it feel warmer. At 98 degrees and 20 percent humidity, the air is so dry you might not even feel the sweat before it evaporates. While this "dry heat" might make it feel cooler than the actual temperature, it still is hot.
Herein lies the danger. When it actually comes to suffering heat exhaustion, there really is not a huge difference in the epidemiological data. Studies show it is temperature, not humidity, that is the number one factor.
The reality is a dry heat can be just as dangerous because people do not feel like they are overheating, even as they are getting more and more dehydrated. This allows heat exhaustion to sneak up on people.
Personally, I prefer dry heat, but hot is hot, and like it, I do not.