help with ID in Skopje (1 Viewer)

I was birding in the fairly large city park in Skopje, Macedonia, on Sept 27, 2002, and saw what I think were wood warblers, but I am trying to make sure they were not willow warblers. There were about 4 of them, loosely scattered in the mid-to-upper canopy of a tall tree, gleaning food from branches. The specimens I saw had strong yellow supercilium, yellow throat and yellow upper breast with a white lower breast and belly. There was also strong yellow colouring in the closed wing, on the edges of the tertials and secondaries. My question is as follows: is this type of yellow colouration, combined with a white belly, enough to rule out a willow warbler, especially a juvenile willow warbler? Would one expect to see much less yellow in the closed wing if they were juvenile willow warblers? I have never seen either species before and am just going on descriptions in field guides, so would greatly appreciate some first-hand expertise. Thank you!

Hi Chris,
I think that they probably were Wood Warblers.The demarcation between yellow face/upper breast+white underparts isn't as clear-cut in Willow,and juv.Willow often show fully yellow underparts.The mention of "yellow"(prob.greenish?)in the closed wing also sounds good for Wood.Both species differ in structure as well,with Wood having longer wings and a shorter tail,also a bit "broader" about the chest.
Harry

Harry:

Thank you very much for your comments. I certainly thought the breast demarcation pretty well indicated wood warbler, but it is nice to have it confirmed by someone with experience. The yellow or yellow-green colour I saw in the closed wing was almost identical to the wood warbler image on plate 81 of Collins Field Guide (5th edition).

Thanks again for your prompt reply.

Cheers,
Chris