The ‘heat dome’ explained: why the Pacific north-west is facing record temperatures

Portland and Seattle are among cities grappling with 100F-plus days in a typically moderate climate

The Pacific north-west, known for its moderate climate, is experiencing a record heatwave. The temperatures have driven crowds to the region's beaches, pools and air-conditioned hotels, as residents in a region with few air-conditioned households try desperately to get some relief.

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