(CNN) As coronavirus cases in Arizona hit a new record high, the state is facing another serious threat: wildfires, with several large blazes stoked by extreme heat and drought burning not far from three of its largest cities.
Scientists say the fires are an ominous start to what could be a very active fire season in the West, as the pandemic, wildfires and climate change all converge to create a recipe for potential disaster.
Arizona has already seen three times as much land burned by fire this year compared to the same time frame in 2019, according to Arizona Department of Forestry and Fire Management statistics.
The largest of the state's fires is the Bush Fire, which is burning northeast of Phoenix in Tonto National Forest. In the roughly five days since it began, it has exploded to become the largest fire currently burning anywhere in the US, and is already one of the largest fires in Arizona history.
As of Thursday morning, the blaze was only 5% contained and had scorched more than 114,000 acres, an area larger than the city of Denver. Evacuation orders have been issued for some towns in Maricopa and Gila counties, as hot and dry conditions are forecast to continue beyond the next week.
In Pima County, a large wildfire sparked by lightning is burning near Tucson. The Bighorn Fire has grown to 31,208 acres with a 40% containment, the US Forest Service said Thursday.
"Yesterday, due to high winds, the fire made a large push to the north, growing by over 7,000 acres," the Pima County Sheriff's Department said in statement Thursday.
"Air operations including fixed-wing airtankers were up early this morning, dropping water and fire retardant to slow the fire's spread," the sheriff's department said.
The Pima County Sheriff's Department and Oro Valley Police Department had issued evacuation orders earlier in the week.
The "fire threatened approximately 850 homes around Oro Valley and the Catalina Foothills, with mandatory evacuations in effect for approximately 200 homes," according to a news release from FEMA.
FEMA has authorized the use of federal funds to assist the state in combating the Big Horn Fire. At least 419 fire personnel are battling the fire which is located in the Santa Catalina Mountains. The fire began on June 5.
As public health officials try to keep the coronavirus from spreading, the pandemic has forced the state's firefighters to adjust how they suppress fires.
This year, they are prepositioning more crews, spreading out camp sites and relying more on aircraft to dump water, according to Tiffany Davila, public information officer for the Arizona Department of Forestry and Fire Management.
"... It can be difficult at times to be socially distant while fighting fire, especially when there can be hundreds, maybe even a thousand firefighters assigned to any incident. But we are working in the safest possible way to make sure our crews remain healthy and our communities and residents remain protected," she said.
Abnormally high temperatures are the main driver of these massive fires, says Daniel Swain, a climate scientist at UCLA and the National Center for Atmospheric Research.
May was one of the warmest in Arizona history, according to the National Oceanic and Atmospheric Administration (NOAA), with temperatures in the state 5.5 degrees Fahrenheit hotter than the 20th century average for the month.
But there are also longer-term trends at play.
According to the National Weather Service in Phoenix, the city has not seen any measurable rainfall in more than two months.
And underlying this is an epic, multi-decade "megadrought," which has parched huge swaths of the Southwest. A recent study found that the last two decades are likely the driest stretch the region has seen in hundreds of years, and that human-caused global warming is to blame.
In the short term, favorable weather to help firefighters get control of the flames is not expected anytime soon.
The next opportunity for rain likely won't come until the monsoon season begins in early to mid-July, Swain says.
"Right now, it looks like it'll be at least a couple more weeks of very dry, hot and occasionally windy conditions, which are probably going to mean that some of the fires burning now in Arizona are going to be burning well into July," he said.
The situation in Arizona is concerning, but the possibility of what could come as fire season shifts North to other parts of the Western US is even more troubling, especially in California, which has been devastated by several deadly fires in recent years.
The National Interagency Fire Center's most recent outlook projects above-average fire activity in Northern California starting in June, and broadening to include much of the Northwest, which could see fires pop up through September.
"Unfortunately, [Arizona is] probably a preview of what's coming to the surrounding states over the coming weeks and months, because of this emerging drought across much of the West and the projections for a warmer than average summer just about everywhere, which is happening pretty often these days with climate change," Swain said.
To Swain, the prospect of a pandemic colliding with the threats posed by an intense fire season are worrying.
There's the smoke, that on its own can pose health risks, and even more so in light of how the coronavirus attacks victims' lungs.
There are the challenges that coronavirus poses for firefighters tasked protecting people from fires.
And then there's the issue of evacuations, and the risk that moving thousands of people out of the path of a fire could potentially lead to more Covid-19 infections.
"It may have been a challenging fire season even without the pandemic, but it's making things that much more difficult."