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
Super typhoon near the Philippines. Gusts of up to 155 mph. . . Tuesday, 23 June 2026
WindRadar showing Typhoon MEKKHALA east of Taiwan. A clearly visible eye, surrounded by areas of extremely high wind speeds.
Tuesday, 23 June 2026

Gusts of up to 155 mph

Super typhoon near the Philippines
Schools closed and more heat disruption. Red warnings now live. . . Wednesday, 24 June 2026
Split image showing a person using a sun umbrella near the Elizabeth Tower in London on the left and a temperature map of England on the right with widespread red heat, temperatures reaching 35°C near London, and a large thermometer icon.
Wednesday, 24 June 2026

Red warnings now live

Schools closed and more heat disruption
Unusually strong thunderstorms possible. Ireland & Scotland. . . Wednesday, 24 June 2026
Weather map of Ireland and the UK showing marked warning areas and a lightning warning symbol. Indication of an increased risk of severe weather on Thursday.
Wednesday, 24 June 2026

Ireland & Scotland

Unusually strong thunderstorms possible
All weather news
This might also interest you
Storm Benjamin impacts the UK. Warnings active. . . Wednesday, 22 October 2025
Split weather map showing UK wind speeds in orange-red shades up to 40 mph on the left and warning levels in green-yellow on the right, with a central wind warning sign.
Wednesday, 22 October 2025

Warnings active

Storm Benjamin impacts the UK
Bright and warm conditions take hold. Spring-like outlook. . . Thursday, 23 April 2026
Split UK map showing warm temperatures up to 21 degrees in orange on the left and clear sunny conditions with temperatures from 12 to 18 degrees on the right, with sun icons across the country.
Thursday, 23 April 2026

Spring-like outlook

Bright and warm conditions take hold
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
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