This looks like an adult Townsend's Solitaire- Myadestes townsendii- which is in the thrush family and is a specialty of western North America. Close relatives are the bluebirds.
many thanks for this. I had a quick look on Wikipedia but just wanted to confirm something. Is the Townsends blue on the back? Please see another image of the sme bird.
No Per-Gunnar, they are not blue on the back. Therefore this now (!) looks like a female Mountain Bluebird Sialia currucoides. The solitaire has a much longer tail than the bluebird and is a little bigger overall.