(Reuters) - 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 said on Sunday. 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.

Temperatures are running as much as 20 degrees 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 (48 degrees Celsius) 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.

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 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.

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.

(Reporting by Tyler Clifford in New York; Editing by Lisa Shumaker)

By Tyler Clifford