Updated

A wind-whipped wildfire near Slide Rock State Park in northern Arizona's Oak Creek Canyon forced the evacuations of businesses and homes north of the area Tuesday evening, authorities said.

Meanwhile, an estimated 100-acre brush fire sparked by a vehicle was 20 percent contained. But Interstate 17 near Cordes Junction remained closed in both directions, causing a traffic backup for miles on one of the main routes to northern Arizona.

The two fires sent numerous agencies rushing to fend off the blazes at a time when dry conditions have Arizona on high alert. Arizona officials are worried about the prospect of a devastating 2014 wildfire season amid a drought that has left the state with dangerously dry conditions.

The so-called Slide Fire was burning on the western slope of the canyon across the creek from Highway 89A, which was closed south of Flagstaff to north of Sedona, U.S. Forest Service officials said. The cause of the fire, which was reported about 4 p.m. Tuesday, wasn't immediately known.

Forest Service officials estimated the fire was at 20 acres, but it appeared much larger and large plumes of smoke were visible in the Slide Rock State Park area, which is a popular tourist and vacation spot.

Evacuations were ordered at West Fork, Pine Flat, Halfway, Cave Springs and other campgrounds and day-use areas in the upper canyon.

Several businesses also were ordered to evacuate by Coconino County authorities, who couldn't immediately estimate how many people were affected.

Two Hotshot crews, four engines, two helicopters and Sedona firefighters were battling the wildfire, which was being fanned by wind gusts of up to 23 mph.

"The fire is burning north," Coconino National Forest spokeswoman Heather Noel said. "It's kind of held on the west side of the creek without a lot of spread. It's burning in timber. We have fuel treatments in the area that's helping slow the spread."

The brush fire about 35 miles north of Phoenix was sparked about 2 p.m. by an RV near the Sunset Point Rest Area and quickly grew because of wind gusts and dry conditions, according to Black Canyon Fire Department officials. Television footage showed a frame of an RV still on fire with charred grass around it.

Crews are trying to stop the spread of flames from the so-called Badger Fire along both sides of the interstate, which was closed in both directions near Sunset Point.

Arizona Department of Transportation officials said there was no timetable for when the freeway would reopen.