Blistering Heat Wave Shatters Records Across U.S. West Coast

A severe heat wave is sweeping the U.S. West Coast, affecting around 36 million people. Temperatures are breaking records, particularly in California, Arizona, and Nevada. The National Weather Service warns of increased wildfire risks, and heightened heat advisories are in effect. The climate crisis is cited as a major cause.

A widespread heat wave is expected to deliver a fresh batch of record temperatures along the U.S. West Coast, as millions of Americans sweat through a heat dome that is also hovering over Arizona and Nevada. About 36 million people — roughly 10% of the country — are under excessive heat warnings coming from the heat dome centered over California, the National Weather Service (NWS) said on Sunday. Fossil fuel-driven climate change is driving extreme heat waves across the world and will continue to deliver dangerous weather for decades to come, research shows.

High temperatures are forecast to meet or exceed daily high records in Washington state, Oregon, California, northern Arizona, and central Idaho. In Death Valley National Park along the California-Nevada border, the NWS projects highs near 130 degrees Fahrenheit (54 degrees Celsius) through Friday. On Saturday, the thermometer reached 128 degrees Fahrenheit there, breaking a 17-year record, and reached 115 degrees Fahrenheit in Las Vegas, which tied a record that was set in 2007.

Temperatures are running as much as 20 degrees above normal this time of year in places like Redding, a city in northern California that hit an all-time high of 119 degrees Fahrenheit (48 degrees Celsius) on Saturday, NWS meteorologist Bryan Jackson said. "We're expecting it to drift east through the early part of next week and persist through the week, so we've got a real expansive and extreme heat wave ongoing, and it's expected to continue this week," he said.

The NWS is also warning of increased wildfire risks due to a mix of hot, dry, and windy conditions. In Southern California, residents were ordered late Saturday to evacuate parts of Santa Barbara County where the Lake Fire has scorched more than 13,000 acres since Friday, according to Cal Fire. The wildfire is 0% contained as officials investigate the cause. Another 36 million people are under heat advisories, while about 1 million people face excessive heat watches, including eastern Oregon, northeastern Nevada, and southwestern Idaho.

Heat warnings signify that conditions are imminent, which differ from heat watches that are issued when conditions are forecast in the coming days. U.N. Secretary-General Antonio Guterres called for urgent action to avert "climate hell." Each of the past 12 months has ranked as the warmest on record in year-on-year comparisons across the globe, according to the Copernicus Climate Change Service, the European Union's climate change monitoring service, which links human activities like the combustion of fossil fuels to climate change-causing greenhouse gas emissions.

Last week, U.S. President Joe Biden's administration proposed the first-ever safety standard intended to protect workers and communities from the impacts of extreme heat.

(With inputs from agencies.)