Over 146 million Americans are under extreme heat alerts as dangerous weather sparks new wildfires, according to media reports.
A severe heat wave has shattered temperature records across the western U.S. and is linked to four deaths in Oregon, The Guardian newspaper reported.
Salem hit 103F (39.4C) on Sunday, breaking the previous record of 99F (37.2C) set in 1960.
Authorities in Multnomah County are investigating four suspected heat-related deaths, according to The Guardian.
Excessive heat warnings from the National Weather Service cover parts of California, Nevada, Arizona, Oregon, Washington, and Idaho, while heat advisories extend to the east coast, including Florida, Georgia, Alabama, and Mississippi.
Firefighters are battling numerous new blazes ignited by the extreme heat. As of Monday, 73 large active fires were burning across the country, covering nearly half a million acres.
Fire conditions are expected to persist throughout the week.
A wildfire in Santa Barbara County, California, has consumed over 20,000 acres of land and is 8% contained, NBC News reported, adding that evacuation orders have been issued for the area.
The fire ignited near Lake Zaca just before 4 p.m. on Friday and expanded over the weekend, according to NBC News.
Despite the deployment of helicopters and air tankers to fight the flames, the fire has continued to grow.
Officials expect the fire to keep moving south and southeast due to rising heat, wind, and dry grass.
California and Nevada are forecasted to experience additional daily record high temperatures in the coming week, CNN reported.
The National Weather Service's Weather Prediction Center warned that by Thursday, the heat in the Pacific Northwest will move to the Intermountain West and northern High Plains.
In recent days, many locations in the West and Pacific Northwest have tied or broken previous heat records, with over 165 daily high temperature records potentially being set or matched this week, according to CNN.
The most intense heat is anticipated in Central and Southern California in the coming days, but unusually high temperatures will also impact Washington state, Idaho, and Utah, The Washington Post reported.
Although the heat might temporarily subside by Sunday across the West, there is little indication of any significant change to the overall weather pattern, the newspaper added.
