Western Kingbirds (Tyrannus verticalis) are common in open country here in Arizona, especially in grassland areas and ranches where they can be seen flycatching from exposed perches like wire fences. I spotted this juvenile Western Kingbird in late July in the grassy foothills of the Santa Rita Mountains south of Tucson.
Juvenile Western Kingbirds are very similar to juvenile Scissor-tailed Flycatchers (Tyrannus forficatus), but Scissor-tailed Flycatchers are quite rare here in Arizona (although my mother did see one here in Tucson this summer) and they do not breed here.
Adult Western Kingbirds are gray above, yellow below, and have brown wings and a very distinctive white-edged, dark-tipped brown tail. This juvenile was still covered in patches of baby fluff, giving it a faded piebald appearance.