You will have no problem with the winters, but if you get hot humid summers, that's where it will suffer. Here in Minnesota, some are able to grow it and some aren't. It's not a treeform plant (even at several inches high); it will be mat forming or shrublike. Expect it to grow bigger and taller than in the wild.
Salix arctica isn't native to California.
Arrowhead alpines sells Salix arctica, but I think you'll be happier with Salix repens, especially if you can find the tiny Iona Form. Repens has a blue tinge and light blue leaf undersides. It's easier to grow in warmer climes, to boot.
