Home
Weather London
WeatherRadar
RainfallRadar
TemperatureRadar
WindRadar
LightningRadar
Weather News
Editor's Pick
Discover the app
Weather widget
Contact us
Apps
Career
    Home / Editor's Pick /

    Weather science: Make frost at home!

08:00
19 February 2023

Weather science
Make frost at home!

An empty tin can is the main piece of equipment needed to make frost at home!
An empty tin can is the main piece of equipment needed to make frost at home! - © picture alliance

It's been unseasonably mild this February, so if you're craving a piece of winter, why not try making frost at home!

All you need is:

  • A clean, empty tin can
  • Ice, crushed if possible
  • Water
  • Salt

Half-fill your tin can with ice, fill a quarter more of the can with water, then liberally sprinkle with salt. Cover your tin with a lid and shake gently to make your solution.

Wait a few minutes (though it can take up to ten) and watch your frost form! Generally the more salt, the quicker the process, while too much water can slow the process.

How does this work?

Frost is a thin layer of ice crystals which form on surfaces below zero, and below the dew point. This means moisture is present, so as air condenses in a sub-zero environment, it forms ice crystals on a surface rather than dew.

In our experiment, putting ice inside your can makes it very cold and the outside surface below freezing. Adding salt lowers the freezing point of water, causing the ice to melt. The water vapour in the air then condenses as ice crystals on the outside.

This process of using salt to lower the freezing point of water is exactly how gritting our roads works (you can read more on that here).

Weather & Radar editorial team
More on the topic
A hot and thundery week. Your weather - Your shots. . . Sunday, 28 June 2026
Split image showing a bright branching lightning bolt illuminating pink storm clouds on the left and a vivid rainbow arching above a rocky coastline and calm sea beneath dark clouds on the right.
Sunday, 28 June 2026

Your weather - Your shots

A hot and thundery week
How to sleep better in warmer weather. Tropical nights ahead. . . Tuesday, 23 June 2026
Person sitting on the floor indoors beside a running electric fan, cooling down in a sunlit room during hot weather, with sunlight streaming through a window.
Tuesday, 23 June 2026

Tropical nights ahead

How to sleep better in warmer weather
New record June temperature in the UK. Likely to be broken again. . . Thursday, 25 June 2026
Heat map of southern England on 24.06 showing extreme temperatures across Hampshire, with Gosport highlighted at 36.1°C and nearby Portsmouth around 35°C amid deep red heat zones.
Thursday, 25 June 2026

Likely to be broken again

New record June temperature in the UK
All weather news
This might also interest you
Mixed conditions on an unsettled week. Your weather - Your shots. . . Sunday, 2 November 2025
plit image showing a double rainbow over a rocky shoreline on the left and sheep grazing in a green field under stormy clouds on the right.
Sunday, 2 November 2025

Your weather - Your shots

Mixed conditions on an unsettled week
Storm Chandra makes impact. Severe gales & heavy rain. . . Tuesday, 27 January 2026
Split image showing strong winds over the UK on a forecast map and widespread rain and snow on a weather radar map.
Tuesday, 27 January 2026

Severe gales & heavy rain

Storm Chandra makes impact
Historic Storm Éowyn arrives. On this day.... . . Saturday, 24 January 2026
Split image showing a person in a yellow jacket struggling against strong winds and heavy rain on a street at night on the left, and an Irish wind forecast map on the right with red and purple shading, gusts up to 75 mph, and a wind warning icon, divided by a curved white line.
Saturday, 24 January 2026

On this day...

Historic Storm Éowyn arrives
All articles
Weather & Radar

Weather & Radar is also available on

Google Play StoreApp Store

Company

Contact us Privacy Policy Legal info Accessibility statement

Services

Uploader

Socials

facebooktwittertikToklinkList