Why is 98 degrees so hot?

My mother-in-law recently asked me an interesting question: If your body temperature is at 98.6 degrees, then why do you feel hot when the outside temperature is at 98 degrees? Shouldn't you feel neutral or comfortable at 98 degrees?

This, I thought, was an interesting question; one worth adding to 'Awesome Science'.

Heat is a by-product of the body's metabolic processes, and so our bodies are constantly radiating heat. When the atmospheric temperature is at a comfortable 68 degrees, our body is able to rid itself of the excess heat, and stay at a healthy 98 degrees. However, when the temperature drops to cold temperatures, such as freezing (or anything below that), our body looses heat at a rate that it cannot keep up with. The result: frost bite and hypothermia. Now, when the atmospheric temperature rises to levels which equal our internal body temperature, the body doesn't have anywhere to distribute the heat. Fortunately, our bodies have a backup coolant system - sweat. Perspiration allows us to cool off quickly and prevent overheating.