Heat wave shatters records, impacts millions in Pacific Northwest and western US.

The Pacific Northwest is experiencing a rare and historic heat wave, with temperatures soaring 15 to 30 degrees higher than average due to a large and strong area of high pressure. Climate change has made the record-breaking temperatures two to five times more likely. The hot and dry conditions are fueling unprecedented wildfires in western Canada, leading to potential air quality issues in parts of the Lower-48 states. Meanwhile, other parts of the country can expect strong to severe storms and spotty flash flood threats through the week.