What causes thunder?

BBC Weather: Wintry showers and snow to hit parts of UK

When you subscribe we will use the information you provide to send you these newsletters. Sometimes they’ll include recommendations for other related newsletters or services we offer. Our Privacy Notice explains more about how we use your data, and your rights. You can unsubscribe at any time.

Thunder, snow and gales are forecast to blast parts of Britain on Wednesday as an Arctic cold snap hits the country. Parts of the UK saw several inches of snow on Tuesday with gale-force winds slamming many areas. So far this month there have been “unusually” cold weather for May which is moving across the country, causing temperatures to drop to between 2C and 4C.

The Met Office predicts heavy showers across the country on Wednesday evening and overnight.

These showers may include hail and will tend to ease across many areas, although a few will linger around coastal areas.

Clear spells are forecast to develop in other areas which will allow frost to develop once more and it will be quite sharp in some places.

Northern areas of Scotland are predicted to see rain and snow later on.

The rain and snow will continue in northern Scotland and will move southwards turning more showery later on.

These showers are expected to be possibly heavy with some sunny intervals.

Further south, there will be longer sunny spells and only scattered showers.

Conditions will feel very chilly throughout Thursday.

Thunderstorms develop when the atmosphere is unstable because warm air exists underneath much colder air.

As the warm air rises it cools and condenses to form small droplets of water.

If there is enough instability in the air, the updraft of warm air is rapid and the water vapour will quickly form a cumulonimbus cloud, which typically can form in under an hour.

Thunderstorms are common on Earth and are caused by lightning which is a stream of electrons flowing between and within clouds, or between a cloud and the ground.

The air surrounding the electron stream is heated to as hot as 50,000 degrees Fahrenheit, which is three times hotter than the surface of the sun.

As the superheated air cools it produces a resonating tube of partial vacuum surrounding the lightning’s path.

UK weather: Confused Brits take to Twitter as 50mph wind rattles UK [INSIGHT]
Solar storm travelling at 1.8 million km per hour has hit Earth [PICTURES]
Long-range weather chart: Roaring heat to sweet Britain this month [FORECAST]

The nearby air rapidly expands and contracts which causes the column to vibrate like a tubular drum head and produces a tremendous crack.

When the vibrations gradually die out, the sound echoes and reverberates.

These changes prompt the rumbling sound known as thunder which can be heard from more than 10 miles away from the lightning which caused it.

Lightning strikes somewhere on the planet approximately 44 times every second, a total of almost 1.4 billion lightning strikes each year.

Weird facts about thunder

  • Thunder is not only heard during thunderstorms but in rare circumstances can be heard when it is snowing.
  • You can judge how close lightning is by counting the seconds between the lightning flash and the thunderclap.
  • Lightning does not always create thunder.
  • The sound of thunder can be anything from a loud crack to a low rumble.
  • Light travels faster than sound so we see lightning before we hear thunder.
  • Thousands of years ago philosophers such as Aristotle believed that thunder was caused by the collision of clouds.
  • Astraphobia is the fear of thunder and lightning.

Source: Read Full Article