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 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 53.3degC there, breaking a 17-year record and killing a motorcyclist who died from exposure to the extreme heat, multiple news agencies reported, citing a government statement.
Temperatures reached 46degC in Las Vegas, which tied a record that was set in 2007.
Temperatures are running as much as 20 degrees Fahrenheit above normal this time of year in places like Redding, a city a northern California that hit an all-time high of 119 degrees Fahrenheit (48degC) on Saturday, NWS meteorologist Bryan Jackson said.
"We're expecting it to merely drift east through the early part of next week and basically 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 have ranked as the warmest on record in year-on-year comparisons across the globe, according to the Copernicus Climate Change Service, 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, US President Joe Biden's administration proposed the first-ever safety standard intended to protect workers and communities from the impacts of extreme heat.
