Ninety-eight percent of Utah is under a red flag warning from the National Weather Service, said Joe Dougherty, a spokesman for the Utah Division of Emergency Management.
The seven-day forecast calls for continued warm, sunny weather.
Utah firefighters braced Wednesday for more high winds as they try to slow a stubborn wildfire that has burned 13 homes and forced the evacuation of 1,500 people from a ski resort town. More than 650 emergency personnel are involved in the fire suppression response. "We were probably 7 miles from the actual fire and it was pretty scary".
Mayer resident Jill Baker fled town after learning of evacuations on Tuesday while filling up her tank at a gas station.
As she left town, she said, residents were pulling off on the side of the road and discussing what to do about their belongings, pets and horses.
The fire quadrupled in size on Tuesday and led to evacuations in multiple communities south of Prescott.
"Yesterday you could not smell it, which means it was probably blowing away from us", Dewey-Humboldt resident Zerril Perkins said. Mayer has about 1,400.
"It looked like five fires", Baker said.
Barbara Rice lives in Prescott, just off Highway 69, which was recently closed when the fire crossed it. It also is a key requirement should federal aid resources be requested.
In Los Angeles County, fires that flared dangerously close to Hollywood Hills and Burbank homes have been knocked down.
A new wildfire that broke out Tuesday has prompted evacuations for dozens more homes in San Bernardino County.
With the blaze slackening near Brian Head, though, managers say about 750 residents will be allowed back to their homes on Friday.
The fire is the largest in the nation at 201 square kilometres.
More than 600 Arizona firefighters are bracing for persistent windy conditions as they battle a northern Arizona fire that has charred 32 square miles (83 square kilometres ) of dense shrubbery.
Track the latest updates on the fire's growth in the map below.
Jennifer Johnson of Phoenix was driving into Prescott Valley on Tuesday for a meeting and noticed smoke on the way in.
"It's really a strategy or a tactic we have potential to use if the fire becomes a threat, and at this point it's not threatening the community", she said.
He said the critical fire area in the Southwest is expected to shrink on Thursday, but not for long.
AP writers Clarice Silber and Bob Christie contributed from Phoenix.