Of course the only time I saw this one was when it was directly in front of the sun and moving quickly. I had thought from the impression of yellow that it was going to be yet another female Common Yellowthroat. Until I saw the picture.
Is this a Parula? The other shot of it taking off shows yellow under the bill and partway down the front.
[attachment=0:1q9d3638]ParulaPossibly.jpg[/attachment:1q9d3638]