The vegetation fire was reported in the 4700 block of W. Crown Valley, where about 3 to 4 acres were reportedly burning uphill at a moderate rate of speed.
At least one structure appeared threatened at one point, as light wind from the south blew to the north.
Firefighters in helicopters were spotted making water drops on the fire, burning medium brush, before flames could spread to nearby homes.
There were no immediate reports of damage or injuries.
The cause of the fire was not immediately known.