In the kind of cold that locks car doors and makes eyelashes frost, a simple pan of boiling water can turn into a white arc hanging in midair. At around −36 °C, the liquid seems to vanish into a plume of steam and glittering ice, a transformation so fast it looks like a camera trick. What is really happening is a race between evaporation, freezing and gravity, all playing out in less than a second.
When people film themselves hurling boiling water into that kind of deep freeze, they are capturing water as it flashes through all three of its familiar phases at once. The spectacle is beautiful, but it is also unforgiving: the same conditions that create a halo of ice can just as easily send scalding droplets back to earth.
What you actually see at −36 °C
On video, the effect is unmistakable. A person steps into the Arctic air, lifts a mug or pot, and throws a fan of boiling water overhead. Instead of splashing down, most of the liquid erupts into a white cloud that curls away on the wind, leaving only a few stray drops to fall. In one widely shared clip, Ashley Fransen does exactly this as Arctic air returns, and the result is a plume that morphs from liquid to steam to a cloud of tiny ice crystals so quickly that the water appears to go through all three phases almost instantly, as meteorologist Lisa Green explains while sharing the Ashley Fransen video.
In the high Arctic, guides now treat the same move as a kind of field demonstration. One clip from Svalbard shows a guide flinging a ladle of boiling water into the freezing air, where it blossoms into a cloud of ice crystals that looks like a burst of artificial snow. The caption spells out the sequence: the hot water evaporates rapidly, the tiny droplets freeze almost instantly, and the result is a mist that looks just like snow when hot water meets the Arctic air.
The physics behind the “instant” freeze
What looks like magic is really a lesson in energy. Boiling water carries a lot of thermal energy, and a surprising amount of that energy is tied up in the phase change itself. To push liquid water to steam, you have to supply the latent heat of vaporization, which is why it often feels as if the energy demand jumps when you go from 99 °C to a rolling boil. As one thermodynamics explainer notes, that extra energy transforms the water to steam, and the requirement noticeably jumps at the point of boiling, especially as you move from 99 °C into full vaporization, a process described in detail in a guide to the enthalpy of vaporization.
Once that steaming water is flung into air that is tens of degrees below zero, the balance flips. The droplets are tiny, so they have a huge surface area compared with their volume, and the surrounding air is so cold that it cannot hold much moisture. As a result, the vapor cools and condenses almost immediately, then freezes into microscopic crystals. Observers on Mount Washington, where winter temperatures can plunge to −29 degrees Fahrenheit, have documented how this extreme cold, combined with the increased surface area of sprayed water, accelerates evaporation and freezing in exactly this way.
From Mpemba effect to ice halos
The spectacle also brushes up against a long running puzzle in physics: the idea that hot water can sometimes freeze faster than cold water, known as the Mpemba effect. Since Mpemba and Osborne first drew attention to it, researchers have shown that this counterintuitive behavior extends beyond simple beakers of water into a range of physical systems, even microscopic ones, as summarized in recent work that revisits the history since Mpemba and Mpemba and Osborne.
In the sky, the same kind of ice crystals that form from thrown boiling water can create their own light show. When sunlight passes through dense materials like glass, water or ice, it slows and bends, splitting into colors. If those crystals are aligned just right, the refracted light can form shimmering arcs that look like bands of fire. One explainer describes how, when light hits a field of crystals, the combined refraction and reflection can create a shimmering, fire like effect that people sometimes call a “fire rainbow,” a phenomenon that depends on the way light behaves when it hits But dense material like ice.
How cold is cold enough?
Not every winter day will deliver the full halo of ice. Meteorologists who demonstrate the trick stress that the colder it is, the better it works, because the water will phase change quicker and the surrounding air will strip away heat more aggressively. In one breakdown, meteorologist Evan Chickvara explains that the effect depends on both temperature and technique, noting that it will phase change quicker and the colder it is, the better it works, advice he gives while discussing how boiling water can freeze in the cold.
Some science educators put a number on it. If the temperature is −40 °C or colder, they say, a pan of boiling water tossed into the air will almost entirely turn into a cloud of ice crystals, with only a few larger chunks of snow or ice surviving the trip. One guide to winter experiments notes that if the temperature is 40 °C below zero, the thrown water will become a fine spray of ice with just a few larger chunks of snow or ice, a threshold that shows up in advice that begins, “If the temperature is 40 °C below zero,” when describing this If the effect.
The sound, the risk and the social media myth
For people who have tried it, the sensory details are part of the appeal. One commenter in a casual online discussion about everyday sounds calls out the moment you throw boiling water in the air when it is under −30 C as the absolute best, describing how the water turns instantly into steam that then freezes and makes a very unique sound as the crystals fall. That description of the absolute best sound, when boiling water is thrown into air colder than −30 C and then freezes, comes from a user reflecting on how the spray freezes and falls.
That drama has made the trick a staple of short videos and science explainers. One physics themed post frames it as a way to see supercooling and rapid freezing in action, noting that it looks like magic but is pure physics, and that the water must be very hot, close to boiling, so that the vapor can turn directly into ice crystals almost immediately. The same clip emphasizes that hot water contains more thermal energy and that, under the right conditions, vapor turns directly into ice crystals, a sequence highlighted in a discussion of how Hot water behaves when flung into extreme cold.
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