Fifth UK Heatwave Could Push Temperatures Back to 35°C as Forecasters Monitor Mid-August Hot Spell

Britain may be heading for another spell of extreme summer heat, with weather forecasts suggesting temperatures could climb back to 35°C across parts of England during the second week of August.

After already experiencing four official heatwaves in 2026, new forecast guidance indicates that another period of unusually hot weather could develop from August 11, raising the possibility of a fifth heatwave if conditions persist long enough to meet the official criteria.

Current projections from the Global Forecast System (GFS) indicate that temperatures will begin rising steadily after a relatively cooler start to August. Large areas of eastern, central and southern England are expected to record daytime highs above 30°C, with some locations potentially reaching 35°C by August 12.

Forecast maps suggest the Midlands and South East could experience the most intense heat, while temperatures in parts of Yorkshire may also exceed 33°C. East Anglia is similarly expected to remain exceptionally warm, with forecasts indicating highs approaching 34°C later in the week.

If these temperatures are sustained for at least three consecutive days above locally defined thresholds, the UK could officially register its fifth heatwave of the year.

The official definition of a heatwave varies across the country. In southeastern England, temperatures must reach at least 28°C for three straight days, while many northern and western regions require a threshold of 25°C, according to the Met Office.

Weather models currently highlight at least 11 English counties as having the greatest likelihood of experiencing temperatures of 35°C or higher if the forecast verifies. These include Warwickshire, Lincolnshire, Northamptonshire, Hertfordshire, Buckinghamshire, Oxfordshire, Gloucestershire, Worcestershire, Herefordshire, Surrey and Cambridgeshire.

Such conditions could increase the risk of heat-related illnesses while placing additional pressure on transport networks, electricity demand and water supplies, particularly after an already exceptionally warm summer.

The latest projections follow another recent spell of intense heat that saw parts of southern and eastern England reach 35°C, allowing several regions to satisfy the official heatwave criteria.

Despite the hot outlook presented by long-range computer models, forecasters continue to stress that confidence decreases significantly beyond the short-range forecast period.

In its latest long-range outlook, the Met Office expects the first half of August to bring a mixture of sunshine, showers and occasional thunderstorms, with temperatures generally remaining above average across much of the UK. While drier and warmer conditions are expected to become more established later in the period, unsettled weather could still interrupt any prolonged heat.

The Met Office urged caution over long-range projections, saying, **“The key message is that further heatwaves are possible but not guaranteed.”** The agency also noted that **“temperatures will very likely remain above normal, with potential for further hot spells, particularly in the south,”** while emphasizing that it is still too early to determine exactly where any heatwave would develop, how intense it could become or how long it might last.

Meteorologists also note that Atlantic weather systems or thunderstorms moving north from mainland Europe could temporarily break down the hot conditions, meaning the eventual intensity and duration of any heatwave remain uncertain.

Experts caution that long-range weather models, including the GFS, are designed to indicate possible trends rather than provide definitive forecasts. Small changes in atmospheric patterns can significantly alter temperature predictions several days in advance.

Nevertheless, the prospect of another prolonged hot spell would add to what has already been one of Britain’s warmest summers in recent years. The country has already recorded four official heatwaves during 2026, with repeated periods of exceptionally high temperatures affecting millions of people.

Weather experts are expected to continue refining forecasts over the coming days as confidence improves. Residents, particularly across southern and central England, are being encouraged to monitor official weather updates and prepare for potentially very hot conditions if the forecast develops as currently indicated.

While there is no certainty that another official heatwave will materialise, the latest forecast guidance suggests Britain could once again experience soaring temperatures before the middle of August, extending an extraordinary summer of persistent heat.