Meteorologists in California announced extreme heat on Wednesday, which is expected to continue in the western United States until next week. The governor of the west coast state, Gavin Newsom, declared a state of emergency as a precaution in order to provide relief measures and resources.

This is an urgent reminder of how "real" the climate crisis is, Newsom said. He warned of bottlenecks in the energy supply and called on the residents of the most populous US state to save electricity, for example not to set their air conditioning to the lowest temperatures.

The National Weather Service expected temperatures close to record levels in many places. Temperatures of around 51 degrees Celsius have been forecast for the weekend in California's Death Valley, which is known for extreme heat. Temperatures in excess of 40 degrees Celsius were measured in parts of southern California on Wednesday.