Heat Wave in Western U.S. Sets Records, While Another Roasts the East

A heat wave that broke records in Palm Springs, Calif., and in Las Vegas over the weekend was spreading on Monday to bake much of the Western United States. Forecasters said the extreme heat would probably persist for several more days at least.

The temperature in Palm Springs reached 124 degrees on Friday, the highest ever recorded there. Las Vegas also broke a heat record when the temperature there climbed to 120 degrees on Sunday. Records were also broken in Oregon and in other parts of California.

The federal forecast map for the West glowed bright red on Monday in the southern parts of Arizona, Nevada and California, signifying daily temperatures that were expected to rise above 110 degrees. And with a high-pressure system still lumbering over the Southwest, the sweltering conditions were expected to last through the workweek, according to the National Weather Service, with temperatures that could run 15 to 30 degrees above average.

The heat wave is forecast to expand from California and Oregon north to Washington and east over the Great Basin and Arizona on Tuesday and Wednesday.

Soaring temperatures will continue to pose a danger to people who are vulnerable or who lack access to cool shelter and electricity, according to Bryan Jackson, a meteorologist with the service’s Weather Prediction Center in College Park, Md.

“But the heat is high enough out West that it is really not just the vulnerable population,” he said. “It’s dangerous to everyone.”

Officials in Western states also warned that the extreme heat and high winds could propel new wildfires.

In Death Valley, Calif., temperatures reached 127 degrees on Friday, a record for the date, and then 128 degrees on Saturday and 129 degrees on Sunday. A motorcyclist who was visiting Death Valley National Park died from heat exposure on Saturday, and another was treated for severe heat illness.

Sweltering conditions were not limited to the West. A separate high-pressure system in the East has broken daily heat records in Raleigh, N.C. and other cities.

In recent years, global warming has been making heat waves hotter, longer and more frequent. Last year was the warmest on record, and global temperatures have continued to break monthly records in many places this year.

As of Monday morning, more than 141 million people across the United States, about four-tenths of the nation’s population, were under extreme heat advisories, watches or warnings, according to the Weather Service.

Yan Zhuang and Judson Jones contributed reporting.