An historic heatwave has scorched northwest region of the US and Canada, toppling records and sending residents searching for relief.

Stores sold out of portable air conditioners and fans, hospitals cancelled outdoor vaccination clinics, cities opened cooling centres, baseball teams abandoned or moved up weekend games, and utilities braced for possible power outages.

Portland, Oregon, reached 42.2 degrees Celsius (108 degrees Fahrenheit ) on Saturday afternoon, according to the National Weather Service. The previous heat record for Oregon’s largest city was 41.7 C (107 F ), a mark hit in 1965 and 1981.

Seattle reached 38.3 C (101 F) Saturday, making it the hottest June day on record and only the fourth time in recorded history the usually temperate city had topped 37.7 C (100 F).

The forecast was for even hotter temperatures on Sunday and Monday. Many all-time heat records could be broken. In Seattle, the highest temperature ever measured was 39.4 C (103 F), in 2009.