Large areas of Britain experienced their first heat wave of the year on Monday, with forecasts predicting record-breaking May temperatures. The Met Office warned that temperatures might reach 35 degrees Celsius (95 degrees Fahrenheit) in parts of England, surpassing the previous May high of 32.8 degrees Celsius (91 degrees Fahrenheit) set in 1944.
The Met Office described the heat as unprecedented, noting that temperature records are typically broken by small margins. The heat had been accumulating throughout the week, with England and Wales experiencing the peak over the weekend. On Saturday, southeast England saw temperatures as high as 30.5 degrees Celsius (86.9 degrees Fahrenheit).
According to the Met Office, temperatures above 30 degrees Celsius in May are rare, last occurring in 2012. By Sunday, eight locations in southeast England officially met the heat wave criteria, having recorded three consecutive days above their local thresholds.
Britain’s heat wave criteria differ from those in the United States. The National Weather Service in the U.S. defines a heat wave as a period of abnormally hot weather lasting more than two days. In Britain, the Met Office declares an official heat wave when a location experiences at least three consecutive days of temperatures at or above the local threshold.
Forecasts highlighted unusually hot temperatures for Monday, with deviations from average temperatures based on data from 1979 to 2000. The analysis included input from the University of Maine Climate Change Institute and the Global Forecast System by the National Centers for Environmental Prediction.