Seven UK counties are expected to see temperatures reach 35C, while much of the rest of the country bakes in low to mid-30C heat, according to new weather maps from WXCharts.com. The maps show large parts of England and Wales turning volcanic red as a heatwave sweeps across the nation.
Counties Set for 35C
The seven counties forecast to hit 35C are: the City of London, Greater London, Hertfordshire, Essex, Surrey, Berkshire, and Buckinghamshire. These areas are expected to experience the highest temperatures on Saturday, July 25, 2026.
Further north, temperatures will still climb to around 28C, with much of England seeing at least mid-20s. The Met Office defines a heatwave as at least three consecutive days with daily maximum temperatures meeting or exceeding a threshold, which for London and surrounding counties is 28C.
Met Office Long-Range Forecast
In a long-term forecast covering the end of July and start of August, Met Office officials warned of sharp temperature spikes. They stated: "Becoming very warm again in parts of the south before the weekend introduces a more widely unsettled and showery period including risk of thunderstorms – though still some good sunny spells and temperatures around or just above average for most."
Another Met Office forecast added: "Perhaps a somewhat more changeable period, with the potential for showers or thunderstorms or even some longer spells of rain at times, these most likely to the north. Drier and brighter interludes are also likely, perhaps more likely across the south and southeast. Temperatures are likely to be above normal with some hot spells possible."
Climate Expert Warning
Climate information scientist Kendon expressed concern about rising temperature extremes. He said: "What is particularly concerning is how temperature extremes are being affected, as these cause the greatest impacts – a pattern we’ve seen again in 2026 so far. In parts of the south-east, the hottest day of the year has warmed by 4.5°C, three times that of annual mean temperature, and we are now coming to expect 35°C at some point in a hot spell in summer."
Energy Demand Surges
The National Energy System Operator (NESO) issued its third electricity margin notice (EMN) of the year, calling for additional electricity supply as Brits use more energy to keep cool. EMNs are part of balancing expected power supply and demand. While this does not mean there is a risk of blackouts, it indicates heightened electricity usage, according to Sky News. The last time NESO issued such a notice before June was January 2025.
The heatwave follows a period of record-breaking conditions in the UK, with the Met Office warning that a new "normal" for climate extremes has been established. The scorching temperatures are expected to persist into early August, though some areas may see thunderstorms and rain, particularly in the north.
