UK heatwave: What next for the weather after hottest May day ever?

A record-breaking heatwave across the UK could soon begin to cool after the hottest May day ever recorded in Britain.

On Tuesday, temperatures reached 35.1C at Kew Gardens in London, setting a new UK May temperature record.

For two days in a row, parts of south-east England went above 34C. And nearly all weather stations across England and Wales also broke their local May temperature records on Monday and Tuesday.

Northern and eastern parts of England could see temperatures drop by around 10 degrees on Wednesday, with highs of 19C to 23C, before temperatures rise again.

The Met Office, which monitors UK weather, says a heatwave happens when an area reaches a certain high temperature for at least three days in a row.

Different parts of the UK have different heatwave temperatures because some places are usually cooler than others.

In London, for example, the temperature must reach at least 28C for three days in a row for it to officially count as a heatwave.

This week's heat has been very unusual because it happened during spring.

Meteorologists - scientists who study weather - say the UK is still officially in spring until June begins.

With temperatures in many places between 10C and 15C hotter than normal for this time of year.

The immediate cause of the heatwave is a 'heat dome' – where an area of high pressure gets "stuck" over Europe, trapping warm air underneath.

But, Ed Hawkins, professor of climate science at the University of Reading, says that this heatwave "stands out".

Speaking to the BBC, Prof Hawkins explained that climate change is making heatwaves happen more often.

He said that this week's "heat events are emerging earlier, intensifying faster and occurring across a much warmer background climate".

Since weather records began in the UK, only a small number of years have ever seen temperatures reach 30C in May.

During this heatwave, many places in England and parts of Wales stayed above 30C for several days.

BBC Weather's Simon King says: "Though London and south-east England will still get temperatures up to 27C, it won't be 28C needed to officially continue the heatwave.

"However, Wales and south-western England will remain fairly hot, away from the cooler air moving in. Highs here could still reach 30C.

"By Thursday, the supply of cooler air will be cut off as hot air re-surges from France once again. This means that temperatures will increase, with 30C back on the cards."