How to Make Snow With Boiling Water

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Use Boiling Water to Make Snow
It needs to be very cold outside to make instant snow with boiling water. You can make some snow below 20 degrees Fahrenheit, but it’s much better if the temperature is -10 or colder.

You may know you can make your own snow using a pressure washer, but did you know you can make instant snow with boiling water? The temperature outdoors needs to be very cold and the water needs to be boiling hot. But, if you meet those requirements, bundle up and bring the kettle to a boil!

Make Snow With Boiling Water

All you need is boiling water and cold weather:

  • Pot of boiling water
  • Cold weather (well below freezing, the colder the better)

For safety, wear gloves in case you spill or splash water on your way out the door. This is less about getting burned and more about not accidentally sticking damp skin to a freezing cold pan outside!

  1. Boil the water. Obviously it will cool slightly once you remove it from heat, but make the trip outside as quickly as possible.
  2. Toss the water up in the air. Be careful handling the water and don’t throw it at people or pets in case your idea of “cold enough outside” isn’t correct.
Making Snow With Boiling Water
Here is what happens when you throw a cup of boiling water into really cold air to make instant snow. (photo: Daniel Lincoln)

How Cold Does It Need to Be?

It needs to be cold! You’ll get some snow from boiling water at 25 °F (-4 °C) if the conditions are right, but probably not a complete conversion. In other words, some of the water may fall as tiny bits of ice. Chances of success are good at -10 °F (-23 °C). The ideal temperature is -30 °F (-34 °C) or below. This temperature is bitterly cold and quickly causes frostbite, so work quickly.

Why Boiling Water Turns Into Snow

The reason you need to use boiling water is because the vapor pressure of the water is the same as atmospheric pressure at the boiling point. When you throw the water into the air, two things happen. First, you increase the surface area of the water so it can freeze into tiny snow-like crystals rather than little icicles. Second, the mass of hot water immediately heats the air around it, allowing the air to hold more water vapor and causing the air mass to expand. The expansion, in turn, absorbs energy, turning the water vapor into water crystals.

Although it seems counter-intuitive, the project doesn’t work with cold water. Most likely, all you’ll get are falling chunks of ice. Cold water doesn’t exert enough vapor pressure to form escape the liquid state. So, simply throwing it into the air won’t separate the particles enough to form snowflakes. You can use cold water to make snow, but you need to disperse it into the air using a pressure nozzle.