When one boils a pot of water on the stove, the water starts to boil into steam at 212 degrees Fahrenheit. The stove provides the heat both to make the water 212 degrees, and the stove provides the heat to change the state of the liquid water to vapor. However, we all know that water (or any other liquid, for that matter) evaporates when it is cold outside, as long as the temperature is 33 degrees or higher. I know that it takes a relatively large amount of heat just to change the state of liquid water to vapor without increasing the temperature of water at all. If there is a puddle of 50 degrees Fahrenheit liquid water on the ground outside, and if the temperature outside is 50 degrees Fahrenheit, any increase in temperature would just increase the temperature of the liquid water, not cause a change of state of the liquid water to vapor. Therefore, when it is 50 degrees Fahrenheit outside, why does liquid water evaporate?