African heat burst: UK braces for first major heatwave of the year as temperatures to soar above 20C

According WXCharts, summer temperatures will exceed 20C for several consecutive days this month, with temperatures as high as 24C to be felt in the southeast by the end of the week.

The start of the summer season has been marred by rain and thunder, as the country experienced its coolest first 10 days of June since 2020 due to a jet stream which has dragged in unsettled weather. While the heatwave may be a welcome change, the Met Office warned that this could be short-lived.

Met Office Deputy Chief Meteorologist Mark Sidaway said: “In stark contrast to the first half of June, where temperatures have widely been below average, we are expecting to see a steady uptick through the second half of this week, rising to around or above average, and it will likely feel very warm for those in the sunshine.

“This initial spell of warm conditions isn’t expected to last too long however, as it turns more changeable through Friday and into the weekend with areas of cloud and rain spilling east across the UK.” The Met Office also said there is a possibility that the warmer weather may continue into next week, and could persist for several days.

This is reflected in the WXCharts maps, which indicate that the expected temperature increase will be caused by a wave of heat moving towards the UK, originating in northern Africa and passing through Spain, France, and Portugal.

According to the Met Office long-range forecast between June 23 and July 2, the UK will turn much warmer despite outbreaks of light rain affecting western and northwestern areas but for most, it will be dry throughout.

It added: “There is a chance that this could persist for much of the rest of the period, turning increasingly hot, however by midway through next week we see a large range of outcomes some of which allow for a return of much cooler conditions and northerly winds for the latter part of the week. However the trend toward much warmer conditions is preferred for now.”

In the UK, a heatwave is identified as an extended period of unusually high temperatures compared to the typical conditions for that specific time and location. The Met Office sets a temperature threshold for each county, and if the daily maximum temperature meets or exceeds this threshold for at least three consecutive days, it is considered a heatwave.

These thresholds range from 28C in London and some home counties to 25C in northern England, Devon and Cornwall, Scotland, Northern Ireland, and most of Wales. In May, Chertsey in Surrey nearly reached its threshold of 28C, recording the highest temperature of 2024 so far at 27.5C.