Heat dome roasts the West, with brutal record-breaking temperatures

An intense, sprawling heat dome is causing the most intense, long-lasting heat wave of the summer in parts of the West.

The big picture: This heat wave will be a record-breaking event lasting into next week in California and surrounding states. It brings with it serious public health dangers, electric grid challenges and wildfire risks, officials warn.

As of Thursday afternoon, about 46 million were under heat warnings, advisories and watches across a five-state region in the West.