It might be a challenge getting it to work right.
Have you tried using the programmable ventillation in the car? It helps in the summer if you know when you're coming back. Also, good window tinting (I got some 3M stuff that works extremely well) limits heat gain. None of that might be a big deal in the PNW, though.
FWIW, one of the worst things for the car is to sit there idling - in the winter, the cold weather package really makes things comfy almost immediately.