Hello Brian, if you are into planes at all there is the Boeing Museum of Flight, not too far from SeaTac, it has quite a few interesting points to it. Safeco Field is right in the area as well along with the SeaHawks Stadium. As far as the weather goes you will have two choices, Liquid Sunshine and Dry Sunshine, but at least there is plenty of greenery. If you have any interest in underwater welding at all there is the Divers Institute on Lake Washington, they would probably be more than willing to give you a tour and answer questions if you have any interest in that area. You mentioned that you might be visiting the Space Needle, if you go there in the evening you will likely be able to look out over the shipyards and piers and see plenty of activity as far as carbon arcing and welding, I found it particularly interesting to watch someone running the carbon arc a couple hundred feet in the air and see the showers of sparks cascading toward the water. Everyone has given you great suggestions for things to see and do. Enjoy your trip to the Pacific Northwest and good luck on your testing. Best Regards, Allan