Just as some cities were about to see relief from the degraded air quality caused by wildfire smoke, another plume is expected to trickle in from the West, highlighting what authorities say is a reality for the remainder of a long and intense wildfire season.
Why it matters: Several studies in recent months are sounding alarms about how harmful microscopic particles from smoke can wreak havoc on the public's health despite being hundreds of miles from the fire sites.
Forecasters are warning Americans to brace for another extreme heat wave this week, as 107 large wildfires burn across nearly 2.3 million acres of the U.S. West.
Driving the news: "Widespread air quality alerts and scattered Red Flag Warnings stretch from the Northwest and Northern Rockies to the High Plains, as well as throughout parts of central California," the National Weather Service said Sunday.
Authorities continued to search into the night for four people missing in California's historic Dixie Fire, as wildfires raged across the West.
Driving the news: Those unaccounted for were all from the fire-devastated town of Greenville, per a statement from the Plumas County Sheriff's office Sunday. The Dixie Fire is the largest blaze burning in the U.S. and the second-biggest wildfire in the state's history, a Cal Fire spokesperson told Axios.
California Gov. Gavin Newsom (D) said after visiting Greenville that the Gold mining-era town had "been completely destroyed" by the Dixie Fire, as authorities searched for three people missing in the blaze on Saturday.
State of play: Evacuation orders were in effect for several Sierra Nevada mountain communities, as the third-largest blaze in California's history continued to threaten homes.