2 Jul 2015

Severe thunderstorms strike as heat breaks

Yesterday saw the UK experience its hottest July day on record, with the temperature soaring to 36.7C (98F) at Heathrow airport in London.

This beat the previous record of 36.5C, set at Wisley in Surrey on 19 July 2006. It was also the highest temperature measured in the UK for nine years.

The heat extended across the rest of the country too, with 29C recorded at Aviemore in Scotland and Usk in Wales.

However, as is often the case with such intense heat here, when it breaks, thunderstorms form.

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Severe thunderstorms

The building heat and humidity of the past two days has meant that a lot of potential energy has been injected into the atmosphere.

For as long as this energy is stored, the heat and humidity remains. But when the energy is released, it fuels showers and thunderstorms – which is what happened in northern parts of England and Scotland last night.

Air rushed upwards quickly, cooling and condensing, forming huge cumulonimbus clouds that produced severe thunderstorms, leading to frequent lightning, large hail, gusty winds and torrential rain.

The easiest way to think about how this works is imagining what would happen if you take the lid off a saucepan of cooking popcorn. The popcorn kernels would represent the air, quickly shooting upwards and expanding.

Thunderstorm pictures and videos

Northern England and Scotland were the areas affected by severe thunderstorms last night, with a great deal of media posted on Twitter.

Warning – the video below contains flashing images

More thunderstorms are expected in the coming days – especially on Friday night into Saturday. If you capture any pictures, you can send them to me on Twitter – @liamdutton

Tweets by @liamdutton