Several western US states including California and Utah were battling wildfires on Monday as millions of Americans in the region were once again under heat alerts.
Evacuation orders were issued east of Los Angeles in Riverside County, where fires destroyed a handful of buildings and burned through more than 2,000 acres (800 hectares) of land, according to local authorities.
Across California, firefighters were battling 21 blazes of various sizes on Monday, according to government agency Cal Fire.
Their efforts were complicated by baking temperatures that hit the western United States over the weekend, with more than 30 million people affected by heat warnings in California, Arizona, Nevada, Oregon and Washington state.
California Governor Gavin Newsom warned earlier in July of a "very active" wildfire season, following two years of respite thanks to rainy winters.
Repeated heat waves since the beginning of June have dried out much of the state's vegetation, making it easier for fires to spread.
Newsom said that, since January, forest fires have ravaged some 207,415 acres in California -- well above the 10,080 acres recorded during the same period last year, and exceeding the five-year average of 38,593 acres burned.
California last week sent its firefighters to neighboring Oregon, where Governor Tina Kotek said the wildfire season had a "very aggressive start." Around 20 fires are being battled in the northwestern state.
One of them, the Cow Valley Fire, obtained so-called "megafire" status last week after it tore through more than 100,000 acres in a rural, largely unpopulated area. Authorities say it is now 80 percent contained.
Utah was also hit by a blaze on Saturday that broke out near state capital Salt Lake City. It prompted evacuation orders for around 40 homes in the hills north of the city, and spread panic among some who saw the flames up close.
"I ran out of the house and thought, 'That's my backyard,'" Utah resident Roger Hobbs told local channel KSL TV, adding: "It's scary to death up here."
Extreme weather events are becoming increasingly common as our planet warms, largely due to human reliance on fossil fuels, according to scientists.
Last month saw the hottest June on record across the globe, according to the EU's Copernicus Climate Change Service, capping half a year of wild and destructive weather, including floods and heat waves.
