
Western Europe is bracing for an unusually early burst of extreme heat, with forecasters warning that temperatures could rise more than 10 degrees Celsius above average in May, breaking old records in some places.
Temperatures in Portugal, Spain, France and the United Kingdom are expected to exceed 30 degrees Celsius on Friday and next week, with 32 degrees Celsius predicted in Paris and London and up to 35 degrees Celsius in southwest France.
In Spain, temperatures can reach 38 degrees Celsius in the Guadiana and Guadalquivir regions.
French national weather forecaster Meteo-France said the unusually high temperatures are being caused by a "heat dome" extending north from Morocco across the Iberian Peninsula to France.
"Since Thursday, May 21, warm air has gradually moved over France from Morocco, via the Iberian Peninsula, and remains trapped under high pressure, creating an atmospheric blockage pattern."
"This high pressure acts like a lid, trapping warm air and heating it through compression. This is known as a heat dome. In the downdrafts, the air sinks. As it compresses towards the lower layers of the atmosphere, it heats up," the weather forecaster said.
The French national weather agency said records are "almost certain" to be broken for both the highest May temperature recorded in France and the country's highest average daily temperature in May.