The Met Office has warned that the upcoming heatwave, with temperatures expected to reach 40C, will feel more oppressive than the UK's hottest day ever recorded in July 2022 due to significantly higher humidity levels. While the temperature on that day reached 40.3C, the humidity was just 5%. This week, humidity is forecast to be around 20%, making the air feel muggier and hindering the body's natural cooling mechanism through sweat evaporation.
Humidity Makes Heat Feel Worse
Humidity measures the amount of water vapor in the air. When temperatures are high, the body sweats to cool down, but high humidity reduces the rate at which sweat evaporates, leaving people feeling hot and sticky. For some, especially the elderly or those with health conditions, this combination can lead to dangerous overheating and heat stress. The Met Office reported that the humidity will remain elevated even at night, offering little respite.
Red Weather Warning Issued
On Monday morning, the Met Office issued a rare red weather warning for extreme heat across parts of the UK, where temperatures could break the June record of 35.6C set in 1976 in Southampton. The warning covers areas where temperatures may reach 40C. The UK Health Security Agency (UKHSA) warned of impacts on health and social care services, with a potential rise in deaths, particularly among those aged 65 and over or with pre-existing conditions.
Temperature Forecast
Tuesday is expected to see highs of 37C in southern England and 35C in southeast Wales. The peak of the heatwave is forecast for Wednesday and Thursday, when temperatures could climb to 38C, with some places possibly reaching 38-40C. By Friday, conditions will ease slightly, with highs of 33C in eastern areas. The Met Office advised significant disruption to daily life is likely, urging the public to take precautions and adapt routines.
Public Health Advice
Authorities have advised people to stay out of the sun and avoid exercise between 11am and 3pm. The Met Office stated: "During the heatwave expected to affect a large part of England and Wales this week, the highlighted area now looks increasingly likely to see a two to three day period where maximum temperatures in the shade exceed 37 Celsius, perhaps rising to 38 to 40 Celsius in some places." The public should take every effort to make precautions and adapt their daily routines where possible to cope with these levels of heat, which up to now have been extremely rare for the UK.
