A new summer heatwave is set to begin in London, with forecasters predicting highs above 30°C next week. The Met Office has extended a yellow heat health alert until July 11, warning of increased health risks, especially for vulnerable people.
Temperature Forecast and Duration
Temperatures are expected to reach 28°C in London on Saturday, rising to 32°C by Monday. The Met Office predicts seven consecutive days of temperatures between 28°C and 32°C. A heatwave in London is defined as at least three consecutive days with maximum temperatures of 28°C or higher.
Unlike the record-breaking heat in late June, this spell may be more bearable due to lower humidity. Westerly winds from a high-pressure system positioned further west are expected to keep temperatures below the extremes of June, while also reducing humidity levels.
Health Alert and Precautions
The UK Health Security Agency issued a yellow heat health alert for London, effective from noon on Saturday until 8pm on July 11. The alert warns of a heightened risk to health, particularly for the elderly, young children, and those with pre-existing medical conditions. Authorities advise staying hydrated, avoiding peak sun hours, and checking on vulnerable neighbors.
During the previous heatwave in late June, temperatures reached 37.7°C in Norfolk on June 26, making it the hottest June day on record. That heatwave, which coincided with the historic heatwave of 1976, prompted a red weather warning for parts of England and Wales.
Climate Change Context
Scientists from the World Weather Attribution group found that a similar heatwave occurring in the climate of 1976 would have been 3.5°C cooler and would not have seen the same daytime peaks and overnight temperatures. Professor Stephen Belcher, Met Office chief scientist, said: “Human induced climate change has made events like this more likely and more intense. To see temperatures like this in the UK in June is sobering. Events like this bring home the implications of climate change, with very high temperatures and humidity bringing significant health implications from heat stress, as well as impacts to a range of sectors such as transport, energy and water supply.”
May also saw a record-breaking heatwave, with temperatures reaching 35.1°C in Kew, London, smashing the previous May record of 32.8°C set in 1922.
