Portland, Oregon, soared to a searing 116 degrees Monday, hotter than it has ever been in cities such as Dallas, New Orleans and downtown Los Angeles. In fact, when it comes to major U.S. cities, only Phoenix and Las Vegas have been hotter.
On the other side of the country, a parallel heat wave was in full swing, with Boston forecast to touch 100 degrees Tuesday.
The culprit? A buckling in the jet stream causing amplified ridges to surge far north on both sides of the country, resulting in dangerous heat infiltrating areas unaccustomed to it. On Tuesday, 12 million Americans across much of the West were under heat watches and warnings, and 44 million were under heat alerts across the Northeast, stretching from Delaware to Maine.
Monday was a textbook example of a summer scorcher, pumping heat into the entirety of the Pacific Northwest and prompting an electrical utility in Spokane, Washington, to warn that people will face more rolling blackouts amid heavy power demand. More than 35 cities tied or set records, with many areas soaring an unprecedented 30 to 40 degrees above average. The record in Seattle was smashed by 5 degrees, hitting 108, and the record high in Portland was also shattered, soaring to a sizzling 116 degrees, 8 degrees higher than the old record.
The heat was so excessive that Portland streetcar power cables melted and the pavement buckled. And the heat has been so persistent that Seattle achieved a new record: three consecutive days of triple-digit temperatures for the first time.