Amber alert in London. Photo: Zeynep Demir Aslim / Shutterstock.com London is bracing for one of the hottest days of the year so far as an Amber Heat Health Alert remains in force across the capital, with forecasters warning that temperatures could climb to 35°C in parts of southeastern England on Wednesday.
Officials are urging residents to take extra precautions during the short but intense heat spell, particularly to protect older adults, babies, young children, and people with underlying health conditions.
In a message shared on social media, the Mayor of London, Sadiq Khan, called on Londoners to check in on vulnerable family members, friends, and neighbors.
"Please look out for older people, young children, babies and others who may find it more difficult to stay cool and hydrated," Khan said.
According to the Met Office, temperatures will rise rapidly during the first half of the week, with Wednesday expected to bring the peak of the heat. Parts of southeastern England could see highs in the mid-30s, while Thursday is expected to remain hot, with temperatures around 29°C across much of the region.
Met Office Deputy Chief Forecaster Gregory Wolverson described the heat as brief but significant.
"This is a short-lived spell of heat, but temperatures will climb quickly through the first half of the week, particularly in the southeast," he said.
"By Wednesday, some areas could see temperatures in the mid-30°Cs, and while the heat will not be widespread across the whole of the UK, it will be enough for parts of the southeast to likely meet official heatwave criteria by Thursday."
Elsewhere across the UK, conditions are expected to be more changeable. Northern and western regions will see a mix of sunshine and showers, with the possibility of isolated thunderstorms in some areas.
Health authorities are reminding people to stay hydrated, avoid direct sunlight between 11 a.m. and 3 p.m., and postpone strenuous activities until cooler parts of the day. Residents are also encouraged to keep homes cool by closing curtains and blinds and opening windows during the evening.
The warning comes as climate experts continue to highlight the growing impact of rising temperatures in the UK. All of the country's warmest years on record have occurred since 2002, while July 2022 saw temperatures exceed 40°C for the first time.
There are also concerns about elevated wildfire risks across England and Wales despite recent rainfall. The National Fire Chiefs Council said emergency services remain under pressure following a busy summer of wildfire incidents and urged the public to avoid using disposable barbecues in open spaces and to dispose of cigarettes responsibly.
"It only takes one spark to start a wildfire," an NFCC spokesperson said.
Conditions are expected to become cooler by Friday, with temperatures returning closer to seasonal averages across most of the UK. However, forecasters caution that the outlook for the weekend remains uncertain, with the possibility of rain and stronger winds from Sunday onward.