Hi,
I would lean toward Summer, though I am not sure. There seems to be a lot of gray here, and it is hard to tell how much of that is an effect of the light. My evidence for Summer is the big thick bill, the apparent lack of really dark color in the wings, the generally pale appearance of the upperparts, and the variations in color between the head and the rest of the bird. I have actually seen some western forms of Summer which are plumaged quite similarly to this bird, so we shouldn't even rule that out. I am currently based in the Southeast where I see a lot of tanagers of both species in the course of a year.....this just doesn't look much like a Scarlet to me. But again, I am not positive.
James Gibson
ex-Fort Kent