Cassin's Kingbird
Tyrannus vociferans
Adults have a gray head with slightly darker cheeks; a dark unforked tail with a buffy fringe and gray-olive underparts. They have a pale throat and deep yellow lower breast. Juveniles are duller and have pale edges on their wings. Measurements: Length: 8.3–9.1 in (21–23 cm) Weight: 1.6 oz (45 g) Wingspan: 41 cm Cassin's kingbird and the western kingbird are similar in appearance. Cassin's is a little larger than the western and the upper parts are a darker gray than the western.
ID text from Wikipedia, CC BY-SA 4.0
Scissor-tailed Flycatcher
Tyrannus forficatus
Adult birds have pale gray heads and upper parts, light underparts, salmon-pink flanks and undertail coverts, and dark gray wings. Axillars and patch on underwing coverts are red. Their extremely long, forked tails, which are black on top and white on the underside, are characteristic and unmistakable. At maturity, the male may be up to 15 in (38 cm) in length, while the female's tail is up to 30% shorter. The wingspan is 38.1 cm (15.0 in) and the weight is up to 43 g (1.5 oz). Immature birds are duller in color and have shorter tails.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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