I would agree with stevej that this is a Juvenile Common Yellowthroat. This bird is inconsistent with an Orange-Crowned Warbler in several field marks. First of all the tail is too long for an Orange-Crowned. Secondly, the colour is much to light for a Pacific bird which would mean it would have to be either one of the interior or eastern subspecies if it were indeed an OCW. Thirdly, the colouration on the bird is splotchy and bright yellow where as on an OCW it would be a constant greenish-yellow with slight streaking on the breast. And fourthly the bird is simply too elongated to be anything other than a Common Yellowthroat, if you look at the warbler species in this area. I think what is fooling you here with the size issue is that young juveniles often appear bigger than somewhat older juveniles and even adults because their feathers are less sleek and refined meaning they are knit less closely together with more air in between and so more volume. This looks somewhat similar to when a bird puffs out it feathers in cold weather and appears to be what is confusing you here. Hope this helps
