Met Office reveals exactly when 'third heatwave' will make Brits 'uncomfortable'

The Met Office has said the third heatwave of 2025 is set to hit the UK by the end of next week, causing uncomfortable sleeping conditions.

Senior meteorologist Marco Petagna said after a number of cool days, the weather is becoming warm again and temperatures rising could lead to a third heatwave - a period of three or more consecutive days of temperatures higher than a location-based threshold. However, the Met Office forecaster said that while it is clear the hot weather will return by the end of the week, it is difficult to predict its duration.

He said: "It looks like we will meet heatwave criteria again by the end of the week. The main uncertainty is how warm it does become and how long the increase in temperature lasts for.

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"The trend to warmer weather, particularly across England and Wales, certainly looks pretty good going into the week ahead. It will start to feel a bit more humid in the week ahead and also night-time temperatures are going to start to pick up, so it's going to become more uncomfortable for sleeping."

The warning comes as weather maps from WXCharts show that large swathes of the country will experience warmer-than-usual conditions starting from Friday, July 11. According to the latest maps, these warm conditions are set to last for around a week, up until July 18.

The Met Office's long-range forecast from July 10 to July 19 says: "A broad northwest/southeast split in the weather looks most likely through much of this period. Towards the northwest, Atlantic frontal systems will bring occasional rain and cloudier skies at times, along with breezier conditions, though there should be some drier, brighter interludes too.

"Further south and east, high pressure will likely dominate with a fair amount of dry and sunny weather to be had. With this, there is a signal for increasing heat and humidity and the potential for another period of hot weather to develop by the second weekend of July, probably lasting into the start of the following week. Given the anticipated high temperatures, the chance of thunderstorms also increases, though widespread rainfall across southern areas looks unlikely."

The Met Office also warned of the risk of thunderstorms on Sunday. The weather service said there is a mixed forecast for Sunday and Monday, before temperatures are expected to climb back into the low 30Cs by the end of next week.

Parts of East Yorkshire, Lincolnshire and the East of England are set for heavy rain, lightning and hail on Sunday, which could cause disruption to transport links. The rest of the country is also forecast to experience cooler air, cloud and showery spells for the rest of the weekend and early next week, before temperatures begin to rise again.

Mr Petagna said: "The headline is a changeable theme to the next couple of days and then the weather will become more settled as we go into next week. It could well reach heatwave criteria again across England and Wales towards the end of next week.

"In the short term, it's quite a mixed picture. There's a lot of cloud around, and bits and pieces of showery rain around. Across the East of England, the weather could turn heavy and thundery and there's a warning out for thunderstorms between 7am to 7pm, because of the unsettled atmosphere.

"We could see an inch or two of rain and several thunderstorms there on Sunday, and that showery scene continues into Monday as well, especially in the north and east of the UK."