Weather tracker: heat dome raises temperatures in Spain and Portugal

Phenomenon is forecast to expand as it strengthens, triggering conditions of more than 30C in parts of Europe

Parts of southern and western Europe have been experiencing unusually high temperatures. Areas of Spain and Portugal have recorded daily maximum temperatures in the high 30s celsius for more than a week, exceeding 40C in parts of southern Spain on Sunday. Italy, France, Germany and the Benelux region also reached the low-to-mid 30s celsius in places at the weekend.

The heat is caused by a large area of high pressure that is stagnating over Europe and preventing the usual pattern of low pressure systems moving eastwards into Europe from the Atlantic. This is known as a blocking high and results in very dry and stable conditions, as the fronts associated with more dynamic weather patterns are forced away by the high pressure.