UK weather: When will the next heatwave arrive - Met Office forecasts hot temperatures 'within days'

In contrast to last year’s washout, 2025’s summer weather has been relatively fine overall.

As well as a prolonged spell of good weather in April, there have already been two - less pleasant - heatwaves. The first was between June 17 and June 22, and the second arrived less than a week late on June 27, and lasted until Wednesday last week.

Now a third heatwave is set to hit the UK by the end of the coming week, the Met Office believes.

It says temperatures are likely to be in the low 30s and the heat is forecast to remain at night, making sleeping uncomfortable.

Marco Petagna, senior meteorologist at the Met Office, said: “I think Wednesday is probably going to be the day when we could start to reach the thresholds of 25C to 28C, depending on where you are. But of course, you need three days at those temperatures for it to be able to be called a technical heatwave.

“So, although the temperature will be reaching the criteria, we probably won’t actually reach an official heatwave until around Friday, to give the three consecutive days at those temperatures.

“But 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 30C, perhaps just nudging into the low 30s.

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

Yet the duration of the hot spell remains difficult to gauge, and there are uncertainties about just how high temperatures will rise.

It also 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.

“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.”