3 things to know about the record-smashing heat wave baking the Pacific Northwest

Climate change is expected to make this rare 1-in-1,000-year event more common

Portland residents cooling off in the Oregon Convention Center

Amid a record-smashing heat wave across the Pacific Northwest, residents in Portland, Ore, find shelter on June 27 in a 24-hour cooling center at the Oregon Convention Center.

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Like a lid on a steaming pot, a high-pressure system is sitting over the U.S.