From the Great Plains to the California coast, a powerful "heat dome" is setting records. This one is stronger and bigger and is appearing earlier than normal.
When a weather station in Death Valley recorded a high of 130 degrees Sunday, it triggered an inquiry to verify the reading. Here's a look into the exacting process of vetting extreme weather claims.
Any visitors to the national park are getting blunt advice: "Travel prepared to survive." It's part of a heat wave that is forcing rolling blackouts in the West.
