Seattle and Portland hit record temperatures on Saturday when a dome of Extremely Hot Air blew across the northwest U.S. Pacific Ocean.
Seattle and Portland are expected to break records, both Sunday and Monday.
It has a heat warning in effect throughout Washington and Oregon as well as parts of Idaho, Wyoming and California.
Saturday’s temperatures climbed to 38.3C (137F) in Seattle, the hottest June day on record.
Residents in the temperate Pacific Northwest tend not to be comfortable handling the heat and many homes lack air conditioning.
Temperatures are forecast to rise 20 to 30 degrees above average across Washington and Oregon states.
State, tribal and federal officials earlier this week launched a process of draining water from Dworshak Dams in Idaho into the bottom of the Snake River in order to lower the water temperature.
Oregon health officials removed Covid capacity limits at large venues fitted with air conditioners like movie theaters and malls, so people can go in and shelter from the heat.