The United Kingdom is experiencing a record-breaking heatwave, with temperatures on Wednesday exceeding the previous record for the hottest June day. The mercury reached 36.1C (97F) in Gosport, Hampshire, surpassing the 35.6C (96.1F) recorded in 1976.
Today, Thursday, is forecast to be even hotter, with a red extreme heat alert in effect until midnight. This alert signifies a danger to life and covers a large area from London and the south coast to Swansea, Somerset, and Birmingham. The Met Office has warned of significant disruption to daily life as the exceptional heat spreads northward.
If temperatures reach 39C (102.2F), it would mark the second hottest day on record in the UK. A temperature of 38C (100.4F) would still place it among the top five hottest days ever recorded and hotter than any day in the 20th century.
Widespread Closures and Travel Warnings
At least 1,000 schools and nurseries in England and Wales are closed or partially closed on Thursday and Friday due to the extreme heat. Rail passengers are being advised to travel only if "absolutely necessary" on these days. Network Rail has warned of a high risk of disruption to services, with trains operating at reduced speeds and on amended timetables. Passengers are urged to plan ahead, allow extra travel time, and bring water.
Red heat health alerts have been issued by the UK Health Security Agency for several regions, including the East of England, London, and the South East, indicating that adverse temperatures are likely to impact public health and well-being. These alerts are in place until Friday evening. An amber warning for extreme heat is also in effect for parts of east and south-east England on Saturday.
Historical Context of Heatwaves
This heatwave is being driven by a "heat-dome" over western Europe. The previous record for the hottest June day was set during a prolonged heatwave in 1976, which saw 16 consecutive days with temperatures above 30C. That summer was characterized by hot air from the Mediterranean and exacerbated by low rainfall from the previous year. The highest temperature recorded in 1976 was 35.9C (96.6F) in Cheltenham.
The 1976 heatwave also led to significant societal impacts, including water rationing, widespread car breakdowns due to overheating, and reports of unusual social behavior. It was also anecdotally linked to a subsequent fall in birth rates.
The current heatwave's provisional temperatures are undergoing verification. The Met Office defines a heatwave as three consecutive days at or above a set temperature.