Knoxville weather is often hot and humid in the summer. Just after sunrise, when the temperature is rising, the rate of evaporation increases. The amount of water vapor in the air, however, is still low. The rate of condensation and the relative humidity therefore are quite low. Sweat on the skin therefore will evaporate.
Evaporation cools the remaining sweat and, through conduction, the skin.
As the density of water vapor in the air increases, the net rate of evaporation decreases, because more and more molecules are entering the liquid. The sweat does no longer cool the skin efficiently. Just after sunset, when the temperature drops, the humidity increases even more, because the rate of evaporation drops, but the density of the water vapor in the air is still high. To use the least amount of gas, do the following. Turn the flame on high.