Samuel Bartusek News Today

Last summer, the jet stream became a jet wave, which helped form a heat dome over the Pacific Northwest. The effect was a catastrophic heat wave that killed as many as 1,400 people.

During a nine-day heat wave in the Pacific Northwest in June 2021, temperatures rose a staggering 18 to 54 degrees above average.A new study in the journal Nature Climate Change describes the larger-scale forces at work — some of which could affect the Southwest.

In late June and early July 2021, the heat wave that struck western North America was not just any midsummer event. For more than nine days, from British Columbia through Washington and Oregon and beyond, the temperature surpassed average regional temperatures for the period by 10°C (18°F), and on single days in few locales, by an incredible 30°C or 54°F.

Extreme heat waves such as the one that hit the Pacific Northwest last year may be 20 times more likely to occur if carbon emissions are not reduced.