I took some time this afternoon to try the ole ‘throw boiling water into the air to make a cloud’ trick. And it turned out pretty well.
Often this takes temperatures near or below-zero to work best and water that is fresh off the stove from boiling. And in our case, the temperatures was right around zero.
So we gave it a shot! And it turned out pretty well.
SO WHAT IS HAPPENING?
As you throw boiling water into cold air, it isn’t making “snow” like a lot of people claim. I mean, if it is cold enough, it can. But that takes temperatures colder than 40-below-zero.
And most folks are doing things like this in temperatures between 10-below and 20-above.
It doesn’t make things look less cool! It just means something different is happening.
Boiling water, as it sits on your stove, it is producing steam as the water is warmed and evaporated. When you take that water outside, that is still happening. You see steam rising from the water as you walk the pot outside. But the only place the water can escape the surface tension is out of the top of the pot. And as you walk, the farther you go, the more the water cools down.
When you hurl this now near-boiling water into the air is that the energetic water can now escape from every angle. And the relative difference in temperature from the water to the air is huge. And teh amount of water vapor that the cold air can hold is very, very small relative to the amount of vapor being lofted into the air.
So, if the vapor can’t fit, it turns into a little ‘cloud’ of steam. That ‘cloud’ is made of tiny water droplets. The same kind of water droplets you find in a real cloud.
The “precipitation” you see falling out of the steam cloud isn’t snow. It is just the water that never turned into vapor.
