(CNN) Sizzling heat is exacerbating the fire risks out West, where weary crews have been battling blazes in Utah, Nevada, Oregon and California.

"Red flag warnings continue over parts of the West," CNN meteorologist Dave Hennen reported. "Critical fire danger and critical fire risk continue to cover large areas in the West."

About 16 million people remained affected by heat warnings and advisories in Southern California, southern Nevada and parts of Arizona.

In the big metro areas of Phoenix and Las Vegas, temperatures are expected to be above 110 degrees. That would be 10 days in a row for such temperatures in Las Vegas.

Relief could be coming, however.

"Cooler weather is expected to push into the Southwest over the next few days," Hennen said.

Utah fires rage

The view of Utah's Brian Head Fire from the Panguitch Incident Command Post.

Large parts of Utah will stay under red flag warning from the National Weather Service into Thursday and 1,500 people have been evacuated from areas of concern, according to Joseph Dougherty, a spokesperson for the Utah Division of Emergency Management.

The Utah Division of Forestry, Fire and State Lands said that 1,427 personnel were fighting the massive Brian Head Fire that started June 17.

The fire has burned 49,626 acres and is 9% contained, with the agency estimating it will take until July 15 to get it fully under control.

While firefighters made good progress over the weekend, Monday saw winds of 30 mph, which increased fire activity, according to Utah Fire. Officials had been worried the winds would push the fire to the northwest. As a precaution, the region to the northwest of the fire, a remote area called Upper Bear Valley, has been evacuated, she said.

"Horse Valley will be an area of concern (Monday), but crews have begun to prepare for this using dozers and retardant dropped from air tankers to establish indirect firelines," the town of Brian Head said on its Facebook page.

At least 13 homes and eight outbuildings have been destroyed in the ski community, which sits near the Dixie National Forest in the southern part of the state.

Hundreds battle Arizona wildfire

More than 900 personnel are battling the fire, which started June 7. The Frye Fire is about 70 miles northeast of Tucson, the second-largest city in Arizona.

Gov. Doug Ducey declared a state of emergency Friday in Arizona to authorize the use of $200,000 of emergency funds to counter increased wildfire activity.

Since April, the state has experienced more than a dozen large wildfires "aided by high temperatures, winds, and available fuels," his office said.

"We thank the many brave men and women who have stepped up and responded to wildfires around Arizona," Ducey said. "I'm issuing today's declaration to make sure they have every resource needed to do their jobs and protect our communities."

The area near the fire is expecting temperatures in the triple digits through Friday, with no sign of rain.

Almost 300 miles north of the Frye Fire, the Goodwin Fire in Mayer, Arizona, held at 4,400 acres Wednesday night, authorities said. An area with 150 homes called Pine Flats had been evacuated. There are currently 525 firefighters and personnel on site with no injuries to date. The Federal Emergency Management Agency is assisting Arizona with efforts to contain the fire.

Fire in rural LA county

A fire sparked by a traffic collision in California's Placerita Canyon is the latest blaze to hit the West amid a deadly heatwave

The Los Angeles County Sheriff's Department said the collision Sunday caused a tree to catch on fire, beginning a blaze that spread toward the Disney Ranch area.

Sheriff's deputies began helping residents of the Disney Ranch, Tenderfoot Trail Road, Running Horse Road and Placerita Canyon areas to evacuate and affected residents were told to seek shelter at Golden Valley High School in Santa Clarita.

By Monday evening, the fire covered 760 acres, with 75% containment, according to the Los Angeles County Fire Department.

Other fires

Wildfires already have caused far more destruction than usual in the first half of 2017, meteorologist Haley Brink of the CNN Weather Center said. Almost 1 million more acres had burned by Thursday, compared with the 10-year average through June 22.

The US Forest Service has reported that at least 13 large wildfires are burning across the Western United States. There are also smaller blazes in various states.

In New Mexico, the Corral Fire reached about 17,000 acres and is burning with low to moderate intensity, according to New Mexico Fire Information.

In central Oregon, the Rhoades Canyon Fire grew to 15,000 acres but was 100% contained Sunday.

In California, the Manzanita Fire reached 1,200 acres and was 0% contained Monday night according to the Riverside County Sheriff's Department. The fire started after a single vehicle collision. Over 300 firefighters were to continue to fight the fire into Tuesday. The fire shut down Highway 79 in both directions between Beaumont and San Jacinto because it was burning on both sides of the road. Voluntary evacuations are in place in the area.

In Burbank, California, a brush fire forced mandatory evacuations on homes on two streets on Wednesday night, according to the Burbank Fire Department. Approximately 50 firefighters and four water-dropping helicopters were mobilized to help contain the fire. The cause remains under investigation.

The heat in the West and Southwest is blamed for the deaths of two people in California, and it could have been a factor in the deaths of two hikers whose bodies were found in New Mexico's Carlsbad Caverns National Park.