Perhaps someone from the PNW can be more precise, but this looks like the species r. augustinii or one of its many hybrids. There are dozens of the latter, all of which do very well on the west coast but not in less temperate areas.

I'd suspect it is one of the dozens of "blue" azalea cultivars popular in this area. None are really "blue" flowered but have flowers in various shades of lilac/violet to purple - 'Purple Gem', 'Blue Moon', Blue Tit', 'Blue Diamond', 'Blue Danube', etc.

My first choice would be 'Purple Gem' - it looks most like the photo. A visit to any local nursery that offers a good selection of rhodies and azaleas should provide you with some flowering examples to compare. Check out Swanson's or Wells Medina in Bellevue.

Purple Gem? Really? Purple Gem is one of the most available and most widely planted varieties in New England and much of the East. I've never seen one grow in the distinctly upright manner seen in Susan C.'s photo. Purple Gem as well as several other possibilities listed above aren't azaleas, either. Purple Gem and its sibling, Ramapo, are hybrid rhododendrons bred by Guy Nearing.

The above are all often listed as azaleas or sold with the azaleas in this area, as their foliage, habit and flowering characteristics more resemble azaleas than other hybrid rhododendrons. Another possibility is 'Oceanlake'.

All azaleas are rhododendrons but not all rhododendrons are azaleas :-)