Saw this bird in Santa Ana Wildlife Refuge near Pharr, TX today. It was less than a mile from the Rio Grande. Like a dummy, I left my Sibley's at home and I'm not keen on warblers. Not a great pic, but the white eyes, yellow crown and wingbars should be good fieldmarks. Resin, somebody?
I haven't had much time down here, haven't been on DG, but have some pics on my Flickr stream, just search for 'reddirpics'.