Is the sky ever blue in Shanghai?

You may have heard people talk about the lack of a true blue sky in China.
This morning was about as clear as it gets here in Shanghai. These pics are
from our bedroom balcony and you can clearly see the Jinmao Tower and
SWFC buildings in the distance. The second picture shows the deepest
blue you will see here near the top of the photo. The third picture shows you
what it looks like if you are not looking straight up. Nice. This is why we don't
leave our windows open on nice "clear" days.