Britain’s latest heatwave as Met Office forecasters deliver their verdict on next week’s weather

Heatwaves could hit parts of Britain next week after a gray start to the weekend, forecasters said. Friday is expected to be mostly dry, with sunny spells in most areas but showers in Northern Ireland, Scotland and western England, the Met Office predicted.

A “grayer start to the weekend” is forecast on Saturday, with further showers and warm temperatures in southern and eastern England, before a “mainly fine day” for most parts of Britain on Sunday. Warmer and wetter weather is forecast for early next week, with temperatures reaching the mid-20s and potential heatwaves in some areas of central and southern England.

But from Wednesday the weather is likely to become “unsettled”, with the potential for heavy showers and thunderstorms. The warmer weather comes as the number of people visiting the NHS website for hay fever advice has doubled this week, according to health officials. On Monday, temperatures are expected to reach a maximum of 27C in the north of England and 28C in the south and south-east of the country.

The bureau’s chief meteorologist, Neil Armstrong, said: “Some central and southern areas are likely to see temperatures approaching heatwave conditions. that parts of the UK could reach heatwave thresholds. However, regardless of whether everyone is experiencing heatwave thresholds, most of the UK will experience the best conditions and highest temperatures on record.

The following weekend, Met Office spokeswoman Andrea Bishop said: “It’s a grayer start to the weekend than we’re used to. There is a band of cloud and light rain or drizzle, becoming showery as it clears east across England, where most parts are dry with variable cloud and sunny spells.”

Temperatures are expected to reach into the twenties and 20s on Saturday night, the forecaster said. More cloud and drizzle is expected across Wales, central and southern England on Sunday morning, before sunnier conditions for the rest of the day, according to the Met Office. The forecaster attributed the warmer temperatures to the jet stream – the high-speed wind in the atmosphere that causes changes in pressure and helps shape weather across the country.

Ms Bishop added: “Generally high pressure is building – moving in from the south west bringing a mainly fine day for most of us on Sunday. The reason for the warm weather is, for most of June, the jet stream has been on the cold side of us. Now it’s pushing north and driving low pressure systems north, allowing high pressure to move in and bringing that warmer air.

On Friday, NHS England, which runs the NHS.uk website, said the hay fever section of their website had been visited an average of 11,736 times a day this week, compared to a daily average of 4,749 visits last weekend. Hay fever is usually worst between March and September, when pollen counts are highest and the weather can be hot, windy and humid.