Ice Ice Baby: Two Cold Photographs

Two recent photos of what happens when you have a few days at around -20°C (-6°F).

Rothera Point surrounded by sea ice as far as you can see. In Hangar Cove at the bottom left of the photo the ice is so thick now that it is almost indistinguishable from land.

Up at the ski area we had retreated to the caboose for a cup of tea. I swilled my mug out with some more hot water and threw it out the door. The chippy suddenly got very excited as he had noticed that as my hot water met the cold air, it froze and created a cloud. Everyone ran back into the caboose to get more mugs of boiling water to throw in the air.

I've shamelessly cut and pasted from the internet, as they have worded it better than I could:

First, the near-boiling water is already close to becoming steam when it is thrown into the air, which means that the water molecules are much closer to evaporating into the vapor state than they would be if the water were cold.

Second, the act of throwing the water into the air causes it to break up into tiny droplets. The water that was contained in the cup (which originally had a relatively small surface exposed to the air) now experiences a tremendous increase in the total surface area exposed to the air. This situation helps to speed up the evaporation process (evaporation is the process of turning from a liquid to a vapor).

Finally, very cold air typically has a low humidity level (that is, a low amount of water vapor present). This is yet another factor aiding the transition from liquid water, to water vapor, to ice crystals. At sufficiently low temperatures, this process seems to occur almost instantaneously. 

Cold water is more viscous than hot water, so doesn't separate and spread out as efficiently as boiling water does, which is why it doesn't happen with cold water.