Foggy October lake burn-off. Timelapse

Enjoy this early morning moody scene set by the steam rising off the surface of Lac Sainte-Pierre in Quebec, Canada.

A misty morning fog conjures a sense of mystery—but why the fog appears isn't so mysterious once you understand what it is and how it forms. It’s a beautiful sight, and one that becomes more common when the weather shifts from warm summer sunrises to crisp, cold autumn mornings. The phenomenon goes by many names, including steam fog, evaporation fog, frost smoke and sea smoke. So what makes it happen?

Fog forms when cool air and warm water meet and, more specifically, when the difference between the temperature and the dew point is less than 4° Fahrenheit.

Water is heated by the sun and stays warmer than the air during the cool night. When the cold layer of still air settles over the lake, warm water vapor from the lake evaporates, entering the cool air above it.

The thin, warm, moist layer of air over the pond then mixes with the cooler air from the land. As it cools, condensation occurs and a fog forms. It looks like steam rising off the water, hence the name 'steam fog.'

This happens not only over bodies of water but even over moist surfaces, like dew-covered meadows or even over your own skin if you get sweaty while jogging on a chilly morning.

Now, next time you go out for a morning stroll along the edge of a lake or a pond and you see this happening, you can appreciate not only the beauty of it but also the science behind it!