How long will the third heatwave of the summer last?

The third heatwave of the summer is expected to hit parts of the UK by the end of this week, with temperatures again climbing over 30C.

The Met Office said the Wimbledon women’s final on Saturday and the men’s final on Sunday could see temperatures of more than 30C and very high UV and pollen levels.

Scotland is also due to hit the heatwave threshold, with temperatures on the east coast forecast to be up to 31C on Saturday and potentially break local records, according to Met Office meteorologist Liam Eslick.

The UK Health Security Agency issued yellow heat health alerts on Wednesday, valid until 15 July. In the south of England and Wales, temperatures of up to 31C on Thursday and 32C on Friday are possible.

The Met Office is forecasting temperatures could reach as high as 31C in parts of the UK on Friday (Met Office)

The alert was originally only issued for the south of England, but UKHSA expanded the yellow warning to cover the entire country on Thursday. It was put in place from 10am on Wednesday until 10am next Tuesday.

Marco Petagna, senior meteorologist at the Met Office, said: “Temperatures are going to continue to climb as we go toward the end of the week and certainly by Friday and Saturday we could see 30 degrees, perhaps just nudging into the low 30s.

“At the weekend, we could just start to see humidity increasing a little bit as well and nighttime temperatures look like they are going to be, so it will be starting to become more uncomfortable by night.”

It is uncertain exactly how warm it will be for how long, though it appears as though the UK will avoid the stifling weather of the high 30s and low 40s seen in the Mediterranean.

Mr Petagna said: “It’s a bit of a question mark going through the weekend early next week as to how long the heat will last and how high the temperatures will get, because some models are sort of pushing the heat away a bit more quickly, whereas others keep the heat going.

Temperatures are expected to climb even higher over the weekend into the low 30s (PA)

Forecasters predict temperatures will climb to 30C in parts of the UK on Saturday (Met Office)

“At this stage it looks as though certainly into next weekend, we should hold on to hot weather across the south of the UK and temperatures could again certainly get into the low 30s in a few spots.

“And we are going to see some very high pollen and very high UV levels as well.

“But at this stage, we’ve managed to escape some of the very highest temperatures, those seen across Spain and Portugal in particular, where it has reached the mid-40s.”

It follows a weekend of cooler air, cloud and rain in most of England, and a yellow warning for thunderstorms in the east of the country on Sunday.

Meanwhile, provisional Met Office figures showed England had its warmest June on record last month.

The UK saw its hottest day of the year so far when 34.7C was recorded at St James’s Park in central London on 1 July, while the capital also experienced the hottest start to Wimbledon on record.

Two amber heat health alerts were issued in consecutive weeks at the end of June amid two separate heatwaves.

From news to politics, travel to sport, culture to climate – The Independent has a host of free newsletters to suit your interests. To find the stories you want to read, and more, in your inbox, click here.